HNIW, CL-20

• Molecular FormulaC₆H₆N₁₂O₁₂
• Average mass438.185 Da
• 1,3,4,7,8,10-hexanitrooctahydro-1H-5,2,6-(epiminomethanetriylimino)imidazo[4,5-b]pyrazine
  CAS 135285-90-4

• Hexanitrohexaazaisowurtzitane
• 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane
• Octahydro-1,3,4,7,8,10-hexanitro-5,2,6-(iminomethenimino)-1H-imidazo[4,5-b]pyrazine
• HNIW
• 六硝基六氮杂异伍兹烷

ABOUT AUTHOR

Tomasz Gołofit

Thermochemistry, Physical Chemistry, Materials Chemistry

Staff Paweł Maksimowski Wincenty Skupiński Wojciech Pawłowski Waldemar Tomaszewski Tomasz Gołofit Katarzyna Cieślak

Faculty of Chemistry, Division of High Energetic Materials, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland

Hexanitrohexaazaisowurtzitane /ˈhɛksɑːˈnaɪtroʊˈhɛksɑːˌæzɑːˌaɪsoʊˈvʊərtsɪteɪn/, also called HNIW and CL-20, is a nitroamine explosive with the formula C₆H₆N₁₂O₁₂. The structure of CL-20 was first proposed in 1979 by Dalian Institute of Chemical Physics.^[1]In 1980s, CL-20 was developed by the China Lake facility, primarily to be used in propellants. It has a better oxidizer-to-fuel ratio than conventional HMX or RDX. It releases 20% more energy than traditional HMX-based propellants, and is widely superior to conventional high-energy propellants and explosives.

Industrial production of CL-20 was achieved in China in 2011, and it was soon fielded in propellant of solid rockets.^[2] While most development of CL-20 has been fielded by the Thiokol Corporation, the US Navy (through ONR) has also been interested in CL-20 for use in rocket propellants, such as for missiles, as it has lower observability characteristics such as less visible smoke.^[3]

CL-20 has not yet been fielded in any production weapons system, but is undergoing testing for stability, production capabilities, and other weapons characteristics.

Synthesis

THEN CONVERTED TO CL20, HNIW

Synthesis of CL20, HNIW

505	Synthesis of CL-20: By oxidative debenzylation with cerium(IV) ammonium nitrate (CAN)   IPC: Int.Cl.8 C07D		A simple debenzylation approach has been discussed for the synthesis of hexanitrohexaazaisowurtzitane (HNIW or CL-20) one of the most powerful high explosives of today with cerium ammonium (IV) nitrate.
	G M Gore, R Sivabalan*, U R Nair, A Saikia, S Venugopalan & B R Gandhe

First, benzylamine (1) is condensed with glyoxal (2) under acidic and dehydrating conditions to yield the first intermediate compound.(3). Four benzyl groups selectively undergo hydrogenolysis using palladium on carbon and hydrogen. The amino groups are then acetylated during the same step using acetic anhydride as the solvent. (4). Finally, compound 4 is reacted with nitronium tetrafluoroborate and nitrosonium tetrafluoroborate, resulting in HNIW.^[4]

(3R,9R)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^3,11.0^5,9]dodecane

• Molecular FormulaC₆H₆N₁₂O₁₂
• Average mass438.185 Da
• (3R,9R)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^3,11.0^5,9]dodecan
  (3R,9R)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^3,11.0^5,9]dodecane
  (3R,9R)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatétracyclo[5.5.0.0^3,11.0^5,9]dodécane
  5,2,6-(Iminomethanetriylimino)-1H-imidazo[4,5-b]pyrazine, octahydro-1,3,4,7,8,10-hexanitro-, (5R,7aR)-

(3R,5S,9R,11S)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^3,11.0^5,9]dodecane

• Molecular FormulaC₆H₆N₁₂O₁₂
• Average mass438.185 Da
• (3R,5S,9R,11S)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^3,11.0^5,9]dodecan
  (3R,5S,9R,11S)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^3,11.0^5,9]dodecane
  (3R,5S,9R,11S)-2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatétracyclo[5.5.0.0^3,11.0^5,9]dodécane
  5,2,6-(Iminomethanetriylimino)-1H-imidazo[4,5-b]pyrazine, octahydro-1,3,4,7,8,10-hexanitro-, (3aR,5S,6R,7aS)

Cocrystal product with HMX

In August 2012, Onas Bolton et al. published results showing that a cocrystal of 2 parts CL-20 and 1 part HMX had similar safety properties to HMX, but with a greater firing power closer to CL-20. ^[5][6]

Cocrystal product with TNT

In August 2011, Adam Matzger and Onas Bolton published results showing that a cocrystal of CL-20 and TNT had

The synthesis of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0^5,9.0^3,11]-dodecane (HBIW) is the first stage in the production of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.05,9.03,11] dodecane (CL-20), which is the most potent explosive known today. Because of the high performance characteristics of CL-20, a number of research projects are being conducted worldwide on CL-20 synthesis, properties and applications

Scale-Up Synthesis of Hexabenzylhexaazaisowurtzitane, an Intermediate in CL-20 Synthesis

Tomasz Gołofit^*† , Paweł Maksimowski^† , Piotr Szwarc^‡, Tomasz Cegłowski^‡, and Joanna Jefimczyk^†

^† Faculty of Chemistry, Division of High Energetic Materials, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland

^‡Chemical Works “NITRO−CHEM” S.A., Wojska Polskiego 65 A, 85−825 Bydgoszcz, Poland

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.7b00101

*E-mail: tomgol@ch.pw.edu.pl.

After successful synthesis of hexabenzylhexaazaisowurtzitane (HBIW) on a laboratory scale (0.25 L reactor), it was performed on a multilaboratory scale (10 L reactor) and subsequently in an experimental installation in which a 300 L reactor was built. Seven syntheses were carried out in the unit on a pilot scale to produce 250 kg of HBIW. The pilot-scale syntheses ran with a yield comparable to those observed for the processes conducted on a large-laboratory scale. Some modifications were suggested that allowed for reduction of the HBIW weight unit by approximately 50%

HBIW was 89%. FTIR υ (cm^–1): 3022, 2835, 1954, 1669, 1602, 1492, 1451, 1396, 1351, 1302, 1264, 1208, 1169, 1140, 1122, 1072, 1057, 1028, 1017, 986, 926, 896, 828, 792, 781, 749, 732, 698. ¹H NMR (CDCl₃, 400 MHz): δ 7.39–7.42 (m, 30 H, phenyl CH), 4.33 (s, 4 H, CH2), 4.26–4.27 (d, 8 H, CH2), 4.21 (s, 4 H, CH), 3.75 (s, 2, H, CH).

References

1. Jump up^ 王征, 和霄雯 (2016-04-19). “北理工的爆轰速度 中国力量的可靠基石”. 北京理工大学新闻网.
2. Jump up^ 黎轩平 (2016-04-23). ““我们要在宇宙空间占一个位置！””. 北京理工大学新闻网.
3. Jump up^ Yirka, Bob (9 September 2011). “University chemists devise means to stabilize explosive CL-20”. Physorg.com. Retrieved 8 July 2012.
4. Jump up^ Nair, U. R.; Sivabalan, R.; Gore, G. M.; Geetha, M.; Asthana, S. N.; Singh, H. (2005). “Hexanitrohexaazaisowurtzitane (CL-20) and CL-20-based formulations (review)”. Combust. Explos. Shock Waves. 41 (2): 121–132. doi:10.1007/s10573-005-0014-2.
5. Jump up^ High Power Explosive with Good Sensitivity: A 2:1 Cocrystal of CL-20:HMX, Crystal Growth & Design (American Chemical Society), 2012, 12 (9), pp 4311–4314, DOI: 10.1021/cg3010882, Publication Date (Web): August 7, 2012, accessed 7 September 2012
6. Jump up^ Powerful new explosive could replace today’s state-of-the-art military explosive, SpaceWar.com, 6 September 2012, accessed 7 September 2012
7. Jump up^ Angewandte Chemie International Edition
8. Jump up^ Things I Won’t Work With: Hexanitrohexaazaisowurtzitane

Further reading

• Bolton, Onas; Adam J. Matzger (September 12, 2011). “Improved Stability and Smart-Material Functionality Realized in an Energetic Cocrystal”. Angewandte Chemie. 123 (38): 9122–9125. doi:10.1002/ange.201104164. Retrieved 8 July 2012.
• Lowe, Derek (11 November 2011) “Things I won’t work with: Hexanitrohexaazaisowurtzitane”

////////////////CL 20, 135285-90-4, HNIW

Hexanitrohexaazaisowurtzitane

Names
IUPAC name 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.03,11.05,9]dodecane
Other names CL-20 Hexanitrohexaazaisowurtzitane 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane Octahydro-1,3,4,7,8,10-hexanitro-5,2,6-(iminomethenimino)-1H-imidazo[4,5-b]pyrazine HNIW Octahydro-1,3,4,7,8,10-hexanitro-5,2,6-(iminomethenimino)-1H-imidazo[4,5-b]pyrazine 5,2,6-(Iminomethenimino)-1H-imidazo[4,5-b]pyrazine, octahydro-1,3,4,7,8,10-hexanitro- isowurtzitane, hexanitrohexaaza- Octahydro-1,3,4,7,8,10-hexanitro-5,2,6-(iminomethenimino)-1H-imidazo(4,5-b)pyrazine
Identifiers
CAS Number	135285-90-4
3D model (JSmol)	Interactive image Interactive image
Abbreviations	CL-20, HNIW
ChEBI	CHEBI:77327
ChemSpider	8064994  9223599 (3R,9R)-dodec  9594121 (3R,5S,9R,11S)- dodec
ECHA InfoCard	100.114.169
PubChem CID	9889323 11048432 (3R,9R)-dodec 11419235 (3R,5S,9R,11S)- dodec
InChI[show]
SMILES[show]
Properties
Chemical formula	C 6N 12H 6O 12
Molar mass	438.1850 g mol−1
Density	2.044 g cm−3
Explosive data
Detonation velocity	9.38 km s−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

• 1.Bayat, Y.; Malmir, S.; Hajighasemali, F.; Dehghani, H. Cent. Eur. J. Energy Mater. 2015, 12, 439– 458
• 2.Bayat, Y.; Zarandi, M.; Khadiv-Parsi, P.; Salimi, A. Cent. Eur. J. Energy Mater. 2015, 12, 459– 472
• 3.Gołofit, T.; Zyśk, K. J. J. Therm. Anal. Calorim. 2015, 119, 1931– 1939, DOI: 10.1007/s10973-015-4418-2
• 4.Maksimowski, P.; Adamiak, J. Propellants, Explos., Pyrotech. 2010, 35, 353– 358, DOI: 10.1002/prep.200900057

Lisdexamfetamine

• Molecular FormulaC₁₅H₂₅N₃O
• Average mass263.379 Da

(2S)-2,6-diamino-N-[(2S)-1-phenylpropan-2-yl]hexanimidic acid

H645GUL8KJ

L-lysine-(+)-amphetamine

NRP104|Vyvanse®

UNII:H645GUL8KJ

UNII-H645GUL8KJ

Vyvanse®

CAS 608137-33-3

(2S)-2,6-Diamino-N-[(1S)-1-methyl-2-phenylethyl]hexanamide dimethanesulfonate

https://www.google.com/patents/WO2005032474A2

Applicants:	NEW RIVER PHARMACEUTICALS INC. [US/US]; The Governor Tyler, 1881 Grove Avenue, Radford, VA 24141 (US) (For All Designated States Except US). MICKLE, Travis [US/US]; (US) (For US Only). KRISHNAN, Suma [US/US]; (US) (For US Only). MONCRIEF, James, Scott [US/US]; (US) (For US Only). LAUDERBACK, Christopher [US/US]; (US) (For US Only). MILLER, Christal [US/US]; (US) (For US Only)
Inventors:	MICKLE, Travis; (US). KRISHNAN, Suma; (US). MONCRIEF, James, Scott; (US). LAUDERBACK, Christopher; (US). MILLER, Christal; (US)

MICKLE, Travis
Dr. Travis Mickle founded KemPharm, Inc. in late 2006. Prior to KemPharm, from January 2003 to October 2005, Dr. Mickle was Director of Drug Discovery and Chemical Development at New River Pharmaceuticals where he also served in a variety of other senior research roles since joining the firm in 2001. During his tenure at New River, Dr. Mickle was responsible for creating a strong preclinical and clinical pipeline of drugs in the areas of ADHD, pain and thyroid dysfunction. His contributions included, as principal inventor, the discovery and development of lisdexamfetamine dimesylate, the highly successful therapy for the treatment of ADHD known as Vyvanse®. In addition, Dr. Mickle was an active participant in FDA and DEA meetings representing the company’s discovery/chemistry group and was also called in as a critical scientific resource during New River’s financings and strategic partnering discussions. Before his departure, Dr. Mickle played an integral part in New River’s development into a successful publicly-traded company which was subsequently acquired for $2.6 billion by its marketing partner, Shire PLC. Dr. Mickle is also the author of more than 150 US and international patents and patent applications, as well as several research papers. Dr. Mickle holds a Ph.D in Bio-Organic Chemistry from the University of Iowa.

ABOUT SUMA KRISHNAN

Mrs. Krishnan has served as our Senior Vice President — Regulatory Affairs since 2012. From 2009 to 2011, Mrs. Krishnan served as Senior Vice President of Product Development at Pinnacle Pharmaceuticals, Inc. From 2007 to 2009, she served as Chief Financial Officer of Light Matters Foundation. Previously, Mrs. Krishnan was Vice President, Product Development at New River Pharmaceuticals Inc. from September 2002 until its acquisition by Shire plc in April 2007.

Mrs. Krishnan has 22 years’ experience in drug development. Prior to serving at New River Pharmaceuticals Inc., Mrs. Krishnan served in the following capacities: Director, Regulatory Affairs at Shire Pharmaceuticals, Inc., a specialty pharmaceutical company; Senior Project Manager at Pfizer, Inc., a multi-national pharmaceutical company; and a consultant at the Weinberg Group, a pharmaceutical and environmental consulting firm.

Mrs. Krishnan began her career as a discovery scientist for Janssen Pharmaceuticals, Inc., a subsidiary of Johnson & Johnson, a multi-national pharmaceutical company, in May 1991. Mrs. Krishnan received an M.S. in Organic Chemistry from Villanova University, an M.B.A. from Institute of Management and Research (India) and an undergraduate degree in Organic Chemistry from Ferguson University (India).

Lisdexamfetamine (contracted from L–lysine–dextroamphetamine) is a prodrug of the central nervous system (CNS) stimulantdextroamphetamine, a phenethylamine of the amphetamine class that is used in the treatment of attention deficit hyperactivity disorder (ADHD) and binge eating disorder.^[4][5] Its chemical structure consists of dextroamphetamine coupled with the essential amino acid L-lysine. Lisdexamfetamine itself is inactive prior to its absorption and the subsequent rate-limited enzymaticcleavage of the molecule’s L-lysine portion, which produces the active metabolite (dextroamphetamine).

Lisdexamfetamine can be prescribed for the treatment of attention deficit hyperactivity disorder (ADHD) in adults and children six and older, as well as for moderate to severe binge eating disorder in adults.^[4] The safety and the efficacy of lisdexamfetamine dimesylate in children with ADHD three to five years old have not been established.^[6]

Lisdexamfetamine is a Class B/Schedule II substance in the United Kingdom and a Schedule II controlled substance in the United States (DEA number 1205)^[7] and the aggregate production quota for 2016 in the United States is 29,750 kilograms of anhydrous acid or base.^[8] Lisdexamfetamine is currently in Phase III trials in Japan for ADHD.^[9]

Uses

Medical

Lisdexamfetamine is used primarily as a treatment for attention deficit hyperactivity disorder (ADHD) and binge eating disorder;^[4] it has similar off-label uses as those of other pharmaceutical amphetamines.^[4][5] Long-term amphetamine exposure at sufficiently high doses in some animal species is known to produce abnormal dopamine system development or nerve damage,^[10][11] but, in humans with ADHD, pharmaceutical amphetamines appear to improve brain development and nerve growth.^[12][13][14] Reviews of magnetic resonance imaging (MRI) studies suggest that long-term treatment with amphetamine decreases abnormalities in brain structure and function found in subjects with ADHD, and improves function in several parts of the brain, such as the right caudate nucleus of the basal ganglia.^[12][13][14]

Reviews of clinical stimulant research have established the safety and effectiveness of long-term continuous amphetamine use for the treatment of ADHD.^[15][16][17] Randomized controlled trials of continuous stimulant therapy for the treatment of ADHD spanning two years have demonstrated treatment effectiveness and safety.^[15][17] Two reviews have indicated that long-term continuous stimulant therapy for ADHD is effective for reducing the core symptoms of ADHD (i.e., hyperactivity, inattention, and impulsivity), enhancing quality of life and academic achievement, and producing improvements in a large number of functional outcomes^{[note 1]} across nine outcome categories related to academics, antisocial behavior, driving, non-medicinal drug use, obesity, occupation, self-esteem, service use (i.e., academic, occupational, health, financial, and legal services), and social function.^[16][17] One review highlighted a nine-month randomized controlled trial in children with ADHD that found an average increase of 4.5 IQ points, continued increases in attention, and continued decreases in disruptive behaviors and hyperactivity.^[15] Another review indicated that, based upon the longest follow-up studies conducted to date, lifetime stimulant therapy that begins during childhood is continuously effective for controlling ADHD symptoms and reduces the risk of developing a substance use disorder as an adult.^[17]

Current models of ADHD suggest that it is associated with functional impairments in some of the brain’s neurotransmitter systems;^[18] these functional impairments involve impaired dopamine neurotransmission in the mesocorticolimbic projection and norepinephrine neurotransmission in the noradrenergic projections from the locus coeruleus to the prefrontal cortex.^[18]Psychostimulants like methylphenidate and amphetamine are effective in treating ADHD because they increase neurotransmitter activity in these systems.^[19][18][20] Approximately 80% of those who use these stimulants see improvements in ADHD symptoms.^[21] Children with ADHD who use stimulant medications generally have better relationships with peers and family members, perform better in school, are less distractible and impulsive, and have longer attention spans.^[22][23] The Cochrane Collaboration‘s reviews^{[note 2]} on the treatment of ADHD in children, adolescents, and adults with pharmaceutical amphetamines stated that while these drugs improve short-term symptoms, they have higher discontinuation rates than non-stimulant medications due to their adverse side effects.^[25][26] A Cochrane Collaboration review on the treatment of ADHD in children with tic disorders such as Tourette syndrome indicated that stimulants in general do not make tics worse, but high doses of dextroamphetamine could exacerbate tics in some individuals.^[27]

Individuals over the age of 65 were not commonly tested in clinical trials of lisdexamfetamine for ADHD.^[4] Lisdexamfetamine is being investigated for possible treatment of cognitive impairment associated with schizophrenia and excessive daytime sleepiness.^[28]

Cognitive

In 2015, a systematic review and a meta-analysis of high quality clinical trials found that, when used at low (therapeutic) doses, amphetamine produces modest yet unambiguous improvements in cognition, including working memory, long-term episodic memory, inhibitory control, and some aspects of attention, in normal healthy adults;^[29][30] these cognition-enhancing effects of amphetamine are known to be partially mediated through the indirect activation of both dopamine receptor D₁ and adrenoceptor α₂ in the prefrontal cortex.^[19][29] A systematic review from 2014 found that low doses of amphetamine also improve memory consolidation, in turn leading to improved recall of information.^[31] Therapeutic doses of amphetamine also enhance cortical network efficiency, an effect which mediates improvements in working memory in all individuals.^[19][32]Amphetamine and other ADHD stimulants also improve task saliency (motivation to perform a task) and increase arousal (wakefulness), in turn promoting goal-directed behavior.^[19][33][34] Stimulants such as amphetamine can improve performance on difficult and boring tasks and are used by some students as a study and test-taking aid.^[19][34][35]Based upon studies of self-reported illicit stimulant use, 5–35% of college students use diverted ADHD stimulants, which are primarily used for performance enhancement rather than as recreational drugs.^[36][37][38] However, high amphetamine doses that are above the therapeutic range can interfere with working memory and other aspects of cognitive control.^[19][34]

Physical

Amphetamine is used by some athletes for its psychological and athletic performance-enhancing effects, such as increased endurance and alertness;^[39][40] however, non-medical amphetamine use is prohibited at sporting events that are regulated by collegiate, national, and international anti-doping agencies.^[41][42] In healthy people at oral therapeutic doses, amphetamine has been shown to increase muscle strength, acceleration, athletic performance in anaerobic conditions, and endurance (i.e., it delays the onset of fatigue), while improving reaction time.^[39][43][44] Amphetamine improves endurance and reaction time primarily through reuptake inhibition and effluxion of dopamine in the central nervous system.^[43][44][45] Amphetamine and other dopaminergic drugs also increase power output at fixed levels of perceived exertion by overriding a “safety switch” that allows the core temperature limit to increase in order to access a reserve capacity that is normally off-limits.^[44][46][47] At therapeutic doses, the adverse effects of amphetamine do not impede athletic performance;^[39][43] however, at much higher doses, amphetamine can induce effects that severely impair performance, such as rapid muscle breakdown and elevated body temperature.^[48][49][43]

Available forms

Vyvanse capsules are available in doses of 10 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, and 70 mg of the active ingredient, lisdexamfetamine dimesylate.^[50] Vyvanse capsules contain several inactive ingredients, including microcrystalline cellulose, croscarmellose sodium, and magnesium stearate.^[50] The capsule shells contain gelatin and titanium dioxide, and may contain FD&C Red 3, FD&C Yellow 6, FD&C Blue 1, black iron oxide, and yellow iron oxide.^[50]

DESCRIPTION/SYNTHESIS

Lisdexamfetamine dimesylate is approved and marketed in the United States for the treatment of attention-deficit hyperactivity disorder in pediatric patients. The active compound lisdexamfetamine contains D-amphetamine covalently linked to the essential amino acid L-lysine. Controlled release of D-amphetamine, a psychostimulant, occurs following administration of lisdexamfetamine to a patient. The controlled release has been reported to occur through hydrolysis of the amide bond linking D-amphetamine and L-lysine.

A procedure for making lisdexamfetamine hydrochloride is described in U.S. Pat. No. 7,223,735 to Mickle et al. (hereinafter Mickle). The procedure involves reacting D-amphetamine with (S)-2,5-dioxopyrrolidin-1-yl 2,6-bis(tert-butoxycarbonylamino)hexanoate to form a lysine-amphetamine intermediate bearing tert-butylcarbamate protecting groups. This intermediate is treated with hydrochloric acid to remove the tert-butylcarbamate protecting groups and provide lisdexamfetamine as its hydrochloride salt. However, this procedure suffers several drawbacks that are problematic when carrying out large scale reactions, such as manufacturing scale, to prepare lisdexamfetamine.

Lisdexamphetamine of formula I, is a conjugate of D-amphetamine and L-lysine and is chemically named as (2S)-2,6-diamino-N-[(lS)-methyl-2-phenylethyl]hexan amide.

Formula- I

Amphetamines stimulate central nervous system (CNS). Amphetamine is prescribed for treatment of various disorders, including attention deficit hyperactivity disorder (ADHD), obesity, nacrolepsy. It is approved as lisdextamphetamine dimesylate of formula IA and

Formula- IA

marketed under trade name Vyvanse for treatment of attention-deficit hyperactivity disorder in pediatric patients.

L-Lysine-D-amphetamine and its pharmaceutically acceptable salts were first disclosed in US patent 7,662,787 wherein it is exemplified as hydrochloride salt. Process for preparation of L- lysine-D-amphetamine includes reaction of BOC-Lys-(BOC)-hydroxysuccinimido ester with D-amphetamine in dioxane using diisopropyl ethyl amine (DIPEA) as a base to obtain BOC- protected lisdexamphetamine which is then purified using flash chromatography and further reacted with a mixture of 4M hydrochloric acid /dioxane to yield L-lysine-D-amphetamine hydrochloride. The process is as shown in following scheme:

4M HCI/dioxane

In equivalent patent US 7,659,253, process for preparation of mesylate salt is disclosed as shown below.

NHS;DCC;

isopropyl acetate

-50°C, 2 hr

Process includes preparation of BOC-Lys-(BOC)-hydroxysuccinimido ester wherein use of reagents like N-hydroxy-succinimide (NHS) and Ν,Ν-dicyclohexyl- carbodimiide (DCC) is carried out, The above processes involve use of flash column chromatography to purify crude BOC- protected L-lysine-D-amphetamine intermediate. Use of column chromatography is very cumbersome, tedoius and time consuming, therefore not advisable at commercial scale. Further Ν,Ν-dicyclohexylcarbodimiide is known to be highly toxic and moisture sensitive compound, and its use leads to formation of a large amount of Ν,Ν-dicyclohexyl urea (DCU) as bye product which has to be removed from reaction mixture.. Therefore use of DCC is not advisable at industrial scale.

International patent publication WO 2010/042120 discloses a process for preparing L-lysine- D-amphetamine or its salts by reacting D-amphetamine with protected lysine or its salt by using an alkylphosphonic acid anhydride as coupling agent in presence of a base and solvent. The process is as shown in following scheme:

The application discloses use of alkylphosphonic acid anhydrides, which are expensive, and needs additional testing to show absence of phosphic impurities in intermediate or final compound to meet regulatory requirements. So it is not appealing to use alkylphosphonic anhydrides for scale up operations.

International patent publication WO2010/148305 discloses a process for preparation of lisdexamphetamine by removal of chlorine from Ν,Ν’-bistrifluoroacetyl-chloro- lisdexamphetamine by using hydrogenation catalyst like Pd/C, under hydrogen gas to form Ν,Ν’-bistrifluoroacetyl-lisdexamphetamine which on further deprotection by using deprotecting agent to form lisdexamphetamine. Alternatively first deprotection by using deprotecting agent and then chlorine is removed by using hydrogenation catalyst like Pd/C under hydrogen gas. The process involves additional steps of inserting chloro group and thereafter removing chloro group; further Pd/C is an expensive reagent, hence not attractive option from cost point of view.

It is therefore, necessary to overcome problems associated with prior art and to provide an efficient process for preparation of lisdexamphetamine and its pharmaceutically acceptable salts using easily available, less expensive, easy to handle raw materials and avoid use of column chromatography.

PATENT

https://www.google.com/patents/US20120157706

• • Example IPreparation of N,N′-Biscarbobenzyloxy-Lisdexamfetamine (LDX-(Cbz)2)

General Experimental Procedure: In an appropriately sized, inert jacketed reactor charge 378.3 g of Cbz-Lys(Cbz)-OSu and 2309 g of isopropyl acetate. Heat the stirred slurry to ˜50° C. In a second reactor mix 100.0 g of D-amphetamine into 165 g of isopropyl acetate. Add the D-amphetamine solution to the batch over 1.75-2.25 hours. After the addition is complete stir the heterogeneous mixture at 50-55° C. until the reaction is complete by HPLC analysis. Charge 1197 g of methanol and heat the batch at a vigorous reflux 1 hour. Cool the batch to 45-55° C. over 2 hours then hold at temperature for 14-16 hours. Cool the batch to 15-25° C. at a rate of 5-10° C. per hour. Filter the slurry. Rinse the wet cake with 449 g of methanol and dry on the filter under nitrogen. To a clean, dry reactor charge the crude solids and 1642 g of methanol. Stir the slurry and heat to a vigorous reflux for 2 hours. Cool the batch to 45-55° C. over 1-2 hours then hold at temperature 12-16 hours. Continue cooling to 15-25° C. at a rate of 5-10° C. per hour. Filter the slurry and wash the wet cake with 547 g of methanol. Vacuum dry the wet cake at ˜55° C. to give product as a white to off-white solid (332 g, 88 mol %).

The crude LDX-(Cbz)product isolated from the reaction mixture by crystallization had a purity of 99.96% according to HPLC analysis.¹H NMR analysis of crude LDX-(Cbz)₂product revealed the presence of 0.57% by weight N-hydroxysuccinimide. The purified LDX-(Cbz)₂product obtained by re-crystallization from methanol had a purity of 99.99% according to HPLC analysis.¹H NMR analysis of the purified LDX-(Cbz)₂product obtained by re-crystallization from methanol revealed that the amount of N-hydroxysuccinimide in the purified LDX-(Cbz)₂product was reduced to 0.05% by weight.

Example 2Preparation of Lisdexamfetamine Dimesylate

General Experimental Procedure: In an appropriately sized, inert autoclave charge 100.0 g of LDX-(Cbz)2, 1 g of 10% (50% wet) palladium on carbon and 607.5 g of n-butanol. Stir the mixture under 100-150 psi of hydrogen at 80-85° C. until the reaction is complete by HPLC analysis. Heat the batch to 95-97° C. and hot filter. Transfer the product rich filtrate to an appropriately sized glass reactor. Charge 7.6 g of methanesulfonic acid maintaining a batch temperature of 32-38° C. To the resulting solution add 1.3 g of LDX-2MSA seed crystal. Stir the batch 4-16 hours at 32-38° C. Charge 30.4 g of methanesulfonic acid to the slurry over not less than 2 hours maintaining a batch temperature of 32-38° C. After the addition stir 1-2 hours at 32-38° C. Charge 436 g of isopropyl acetate over not less than 2 hours, then stir 1-2 hours at 32-38° C. Cool the batch to 15-25° C. and hold 1 hour. Filter the slurry. Wash the wet cake with a premixed combination of n-butanol (91.5 g) and isopropyl acetate (32.7 g) followed by a wash of isopropyl acetate (87.2 g). Vacuum dry the wet cake at ˜50° C. to give product as a white to off-white solid (78.8 g, 92 mol %).

PATENT

WO 2017098533

Sun Pharmaceutical Industries Ltd

Process for preparation of lisdexamphetamine and its salts via a novel aziridine intermediate is claimed. Lisdexamphetamine attention deficit hyperactivity disorder (ADHD). Represents the first patenting to be seen from Sun pharmaceutical that focuses on lisdexamphetamine. At the time of publication Pawar and Patel are affiliated with Chattem chemicals .

PATENT

WO 2005032474

IN 2011DE02040

WO 2013011526

IN 2009CH01986

WO 2010042120

PATENT

https://www.google.com/patents/WO2013011526A1?cl=en

Formula II A

Formula IV

Formula IVA

EXAMPLES

Examplel Preparation of 2,6-bis-tertiarvbutoxycarbonylamino hexanoic acid

To a solution of L-lysine monohydrochloride (25g, 0.14mol) and sodium hydroxide (15g) in water (250 ml), ditertiary butyl dicarbonate (70.0 g, 0.32 mol) was added at 15-25°C. The temperature was slowly raised to 55-60 °C and the reaction mixture was stirred for 12 hours.. After completion of reaction, ( monitored by TLC), the reaction mixture was cooled to 10-

15°C and pH was adjusted to 2.5-3.5 with 2N hydrochloric acid. The reaction mass’ was then extracted with dichloromethane (2 x 125 ml) and combined organic layer was successively washed with water (150 ml) and brine (150 ml). Dichloromethane layer was distilled under vacuum at 30-40 °C to obtain 29.7g of title compound as a viscous oily mass having purity 96.5% by HPLC.

Example 2: Preparation of (5-tert-butoxycarbonylamino-5-(l-methyl-2-phenyl- ethylcarba moyl)-pentyll-carbamic acid tert-butyl ester;

To a solution of 2,6-bis-tertbutoxy carbonylamino hexanoic acid (7.5g) in dichloromethane (150 ml) , triethyl amine (8.0 ml) was added at 25-30°C and the reaction mixture was stirred for 15 minutes. The solution was cooled to -15 to -10°C and isobutylchloroformate (4.35 g) was slowly added under nitrogen atmosphere and stirred for 30 minutes at -15°C to – 10°C. A solution of D-amphetamine (3.85 g) in dichloromethane (10 ml) was slowly added and. the reaction mixture was stirred at 15 to -10°C for 60 minutes. The reaction completion was checked by TLC. After completion of the reaction temperature was raised to 25-30°C and reaction mixture was successively washed with 0.5 N hydrochloric acid solution (2 x 75 ml), sodium bicarbonate solution (5%w/w 75ml), water (50 ml) and brine solution (50 ml). The combined dichloromethane layer was dried over sodium sulfate (10.0 g) and distilled at 30- 40°C to obtain a semisolid compound which was stirred with a mixture of n-heptane (85 ml) and ethyl acetate (5ml) at 25-30°C for 30 minutes. The solid, thus obtained, was filtered and dried to get 10.21 g of title compound having purity 89.77% by HPLC. The crude compound was dissolved in ethanol (45ml) at 50-55°C and water (50ml) was added. The reaction mixture was slowly cooled to 35-40°C, stirred for 30 minutes. The solid, thus obtained, was filtered and dried to get 7.35g of pure title compound as a white crystalline solid having purity 99.5 % by HPLC.

Example 3: Preparation of lisdexamphetamine dimesylate

(5-Tert-butoxycarbonylamino-5-( 1 -methyl-2-phenyl-ethylcarbamoyl)-pentyl]-carbamic acid tert-butyl ester (2.5g,) was dissolved in a mixture of isopropyl alcohol (10ml) and ethyl acetate (10ml) at 40-45°C and the reaction mass was cooled to 15-20°C. To this cold solution, methane sulphonic acid (2.5g) was added slowly and stirred for 12 hours at 15- 20°C. The reaction completion was checked by HPLC. The resulting solid was filtered, washed with a mixture of chilled isopropyl alcohol (5ml) and ethyl acetate (5ml) and dried under vacuum to obtain 1.68 g of title compound as a white crystalline solid having purity 99.72 % by HPLC.

Example 4: Preparation of lisdexamphetamine dimesylate:

(5-Tert-butoxycarbonylamino-5-( 1 -methyl-2-phenyl-ethylcarbamoyl)-pentyl]-carbamic acid tert-butyl ester (2.5 g,) was dissolved in ethanol (20 ml) at 25-30°C. To the reaction mixture, methane sulphonic acid (2.5 g) was slowly added and the reaction mixture was heated to 55- 60°C and stirred for 3 hours at 55-60°C. The reaction mixture was cooled to 25-30°C, stirred for 2 hours, filtered, washed with ethanol (10ml) and dried under vacuum to obtain 1.55g of lisdexamphetamine dimesylate having purity 99.61 % by HPLC.

Example 5: Purification of lisdexamphetamine dimesylate

Lisdexamphetamine dimesylate (1.40g,) was dissolved in ethanol (10 ml) at 50-55 °C and ethyl acetate (10 ml) was slowly added at 50-55 °C. The reaction mixture was cooled to 20- 25°C and stirred for 30 minutes. The resulting solid was filtered, washed with a mixture of ethanol and ethyl acetate (3 ml, 1: 1) and dried under vacuum at 55-60°C to obtain 1.28g of pure lisdexamphetamine dimesylate as a white crystalline solid having purity 99.90 % by HPLC.

Example 6: Preparation of lisdexamphetamine dimesylate

To a stirred solution of L-lysine monohydrochloride (50g) and sodium hydroxide (30 g) in water (500ml) at 15-25°C, ditertbutyl dicarbonate(140g) was added. The temperature was slowly raised to 55-60°C and reaction mixture was stirred for 12 hours. After completion of reaction, the reaction mixture was cooled to 10-15°C and pH was adjusted to 2.5-3.5 with 2N hydrochloric acid. The reaction mixture was then extracted with dichloromethane (2 x 250 ml) and combined dichloromethane layer was successively washed with water (300 ml) and brine (300 ml). To the organic layer triethyl amine (58g) in dichloromethane (500 ml) was added. The solution was cooled to -15 to -20°C and isobutylchloroformate (42.5 g) was slowly added at -15 to -20°C and stirred for 1 hour. A solution of D-amphetamine (41.85 g) in dichloromethane (100 ml) was slowly added to reaction mixture at -15 to -20 °C and stirred. After completion of the reaction, the reaction mixture was successively washed with 0.5 N hydrochloric solution (2 x 450 ml), sodium bicarbonate solution (5%w/w, 450 ml), water (450 ml) and brine solution (450 ml). The organic layer was dried over sodium sulfate and distilled under vacuum at 30-40°C to afford a residue. To this residue, ethanol (480 ml) was added followed by slow addition of methane sulphonic acid (55 g) under nitrogen atmosphere. The reaction temperature was raised 55-60°C and after completion of reaction, the reaction mixture was cooled to 20-25°C and stirred for 2 hours. The resulting solid was filtered, washed with ethanol (50 ml) and suck dried for 30 minutes, further washed with ethanol and dried to obtain lisdexamphetamine dimesylate.

Mechanism of action

Pharmacodynamics of amphetamine in a dopamine neuron
v · t · e

via AADC

Amphetamine enters the presynaptic neuron across the neuronal membrane or through DAT. Once inside, it binds to TAAR1 or enters synaptic vesicles through VMAT2. When amphetamine enters synaptic vesicles through VMAT2, it collapses the vesicular pH gradient, which in turn causes dopamine to be released into the cytosol (light tan-colored area) through VMAT2. When amphetamine binds to TAAR1, it reduces the firing rate of the dopamine neuron via potassium channels and activates protein kinase A (PKA) and protein kinase C (PKC), which subsequently phosphorylate DAT. PKA-phosphorylation causes DAT to withdraw into the presynaptic neuron (internalize) and cease transport. PKC-phosphorylated DAT may either operate in reverse or, like PKA-phosphorylated DAT, internalize and cease transport. Amphetamine is also known to increase intracellular calcium, an effect which is associated with DAT phosphorylation through a CAMKIIα-dependent pathway, in turn producing dopamine efflux.

Lisdexamfetamine is an inactive prodrug that is converted in the body to dextroamphetamine, a pharmacologically active compound which is responsible for the drug’s activity.^[119] After oral ingestion, lisdexamfetamine is broken down by enzymes in red blood cells to form L-lysine, a naturally occurring essential amino acid, and dextroamphetamine.^[4] The conversion of lisdexamfetamine to dextroamphetamine is not affected by gastrointestinal pH and is unlikely to be affected by alterations in normal gastrointestinal transit times.^[4][120]

The optical isomers of amphetamine, i.e., dextroamphetamine and levoamphetamine, are TAAR1 agonists and vesicular monoamine transporter 2 inhibitors that can enter monoamine neurons;^[121][122] this allows them to release monoamine neurotransmitters (dopamine, norepinephrine, and serotonin, among others) from their storage sites in the presynaptic neuron, as well as prevent the reuptake of these neurotransmitters from the synaptic cleft.^[121][122]

Lisdexamfetamine was developed with the goal of providing a long duration of effect that is consistent throughout the day, with reduced potential for abuse. The attachment of the amino acid lysine slows down the relative amount of dextroamphetamine available to the blood stream. Because no free dextroamphetamine is present in lisdexamfetamine capsules, dextroamphetamine does not become available through mechanical manipulation, such as crushing or simple extraction. A relatively sophisticated biochemical process is needed to produce dextroamphetamine from lisdexamfetamine.^[120] As opposed to Adderall, which contains roughly equal parts of racemic amphetamine and dextroamphetamine salts, lisdexamfetamine is a single-enantiomer dextroamphetamine formula.^[119][123] Studies conducted show that lisdexamfetamine dimesylate may have less abuse potential than dextroamphetamine and an abuse profile similar to diethylpropion at dosages that are FDA-approved for treatment of ADHD, but still has a high abuse potential when this dosage is exceeded by over 100%.^[120]

Pharmacokinetics

The oral bioavailability of amphetamine varies with gastrointestinal pH;^[118] it is well absorbed from the gut, and bioavailability is typically over 75% for dextroamphetamine.^[124] Amphetamine is a weak base with a pK_a of 9.9;^[125]consequently, when the pH is basic, more of the drug is in its lipid soluble free base form, and more is absorbed through the lipid-rich cell membranes of the gut epithelium.^[125][118] Conversely, an acidic pH means the drug is predominantly in a water-soluble cationic (salt) form, and less is absorbed.^[125] Approximately 15–40% of amphetamine circulating in the bloodstream is bound to plasma proteins.^[126]

The half-life of amphetamine enantiomers differ and vary with urine pH.^[125] At normal urine pH, the half-lives of dextroamphetamine and levoamphetamine are 9–11 hours and 11–14 hours, respectively.^[125] An acidic diet will reduce the enantiomer half-lives to 8–11 hours; an alkaline diet will increase the range to 16–31 hours.^[127][128] The biological half-life is longer and distribution volumes are larger in amphetamine dependent individuals.^[128] The immediate-release and extended release variants of salts of both isomers reach peak plasma concentrations at 3 hours and 7 hours post-dose respectively.^[125] Amphetamine is eliminated via the kidneys, with 30–40% of the drug being excreted unchanged at normal urinary pH.^[125] When the urinary pH is basic, amphetamine is in its free base form, so less is excreted.^[125] When urine pH is abnormal, the urinary recovery of amphetamine may range from a low of 1% to a high of 75%, depending mostly upon whether urine is too basic or acidic, respectively.^[125] Amphetamine is usually eliminated within two days of the last oral dose.^[127]

The prodrug lisdexamfetamine is not as sensitive to pH as amphetamine when being absorbed in the gastrointestinal tract;^[129] following absorption into the blood stream, it is converted by red blood cell-associated enzymes to dextroamphetamine via hydrolysis.^[129] The elimination half-life of lisdexamfetamine is generally less than one hour.^[129]

CYP2D6, dopamine β-hydroxylase (DBH), flavin-containing monooxygenase 3 (FMO3), butyrate-CoA ligase (XM-ligase), and glycine N-acyltransferase (GLYAT) are the enzymes known to metabolize amphetamine or its metabolites in humans.^{[sources 9]} Amphetamine has a variety of excreted metabolic products, including 4-hydroxyamphetamine, 4-hydroxynorephedrine, 4-hydroxyphenylacetone, benzoic acid, hippuric acid, norephedrine, and phenylacetone.^{[125][127][134]} Among these metabolites, the active sympathomimetics are 4‑hydroxyamphetamine,^[138] 4‑hydroxynorephedrine,^[139] and norephedrine.^[140] The main metabolic pathways involve aromatic para-hydroxylation, aliphatic alpha- and beta-hydroxylation, N-oxidation, N-dealkylation, and deamination.^[125][127] The known metabolic pathways, detectable metabolites, and metabolizing enzymes in humans include the following:

Metabolic pathways of amphetamine in humans^{[sources 9]}

4-Hydroxyphenylacetone

Phenylacetone

Benzoic acid

Hippuric acid

Amphetamine

Norephedrine

4-Hydroxyamphetamine

4-Hydroxynorephedrine

Para-
Hydroxylation

Para-
Hydroxylation

Para-
Hydroxylation

CYP2D6

CYP2D6

unidentified

Beta-
Hydroxylation

Beta-
Hydroxylation

DBH

DBH

Oxidative
Deamination

FMO3

Oxidation

unidentified

Glycine
Conjugation

XM-ligase
GLYAT

The primary active metabolites of amphetamine are 4-hydroxyamphetamine and norephedrine;^[134] at normal urine pH, about 30–40% of amphetamine is excreted unchanged and roughly 50% is excreted as the inactive metabolites (bottom row).^[125] The remaining 10–20% is excreted as the active metabolites.^[125] Benzoic acid is metabolized by XM-ligase into an intermediate product, benzoyl-CoA,^[136] which is then metabolized by GLYAT into hippuric acid.^[137]

Chemistry

Comparison to other formulationsLisdexamfetamine dimesylate is a water-soluble (792 mg/mL) powder with a white to off-white color.^[50]

Lisdexamfetamine dimesylate is one marketed formulation delivering dextroamphetamine. The following table compares the drug to other amphetamine pharmaceuticals.

History, society, and culture

Lisdexamfetamine was developed by New River Pharmaceuticals, who were bought by Shire Pharmaceuticals shortly before lisdexamfetamine began being marketed. It was developed for the intention of creating a longer-lasting and less-easily abused version of dextroamphetamine, as the requirement of conversion into dextroamphetamine via enzymes in the red blood cells increases its duration of action, regardless of the route of ingestion.^[148] The drug lisdexamfetamine dimesylate is the first prodrug of its kind.

On 23 April 2008, Vyvanse received FDA approval for the adult population.^[149] On 19 February 2009, Health Canada approved 30 mg and 50 mg capsules of lisdexamfetamine for treatment of ADHD.^[150] On 8 February 2012, Vyvanse received FDA approval for maintenance treatment of adult ADHD.^[151] In February 2014, Shire announced that two late-stage clinical trials had shown that Vyvanse was not an effective treatment for depression.^[152] Lisdexamfetamine was granted approval in a number of European countries for the treatment of ADHD in children and adolescents over the age of 6 years, as well as adults who are continuing treatment from childhood, after a positive outcome of the regulatory procedure.^[153] Shire also recently announced receipt of a positive result from a European decentralised procedure for lisdexamfetamine for adult patients with ADHD in the United Kingdom, Sweden and Denmark, expanding the indication of lisdexamfetamine to include newly diagnosed adult patients.^[154]

In January 2015, lisdexamfetamine was approved by the U.S. Food and Drug Administration for treatment of binge eating disorder in adults.^{[28][155][156]}

In January 2017, a new dosage form of lisdexamfetamine in the form of a chewable tablet (as opposed to a capsule) was approved by the FDA.^[157]

Brand names

Lisdexamfetamine is sold as Tyvense (IE), Elvanse (UK), Venvanse (BR), Vyvanse (CA, US).^[158]

Clinical research

Some clinical trials that used lisdexamfetamine as an add-on therapy with a selective serotonin reuptake inhibitor (SSRI) or serotonin-norepinephrine reuptake inhibitor (SNRI) for treatment-resistant depression indicated that this is no more effective than the use of an SSRI or SNRI alone.^[159] Other studies indicated that psychostimulants potentiated antidepressants, and were under-prescribed for treatment resistant depression. In those studies patients showed significant improvement in energy, mood, and psychomotor activity.^[160]

Notes

References

Lisdexamfetamine

Clinical data
Trade names	Tyvense, Elvanse, Venvanse, Vyvanse
AHFS/Drugs.com	Monograph
MedlinePlus	a607047
License data	US FDA: Lisdexamfetamine
Pregnancy category	AU: B3 US: C (Risk not ruled out)
Dependence liability	Physical: none Psychological: moderate
Addiction liability	Moderate
Routes of administration	Oral (capsules)
ATC code	N06BA12 (WHO)
Legal status
Legal status	AU: S8 (Controlled) CA: Schedule I DE: Anlage III (Special prescription form required) UK: Class B US: Schedule II In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability	96.4%[1]
Metabolism	Hydrolysis by enzymes in red blood cells initially. Subsequent metabolism follows Amphetamine#Pharmacokinetics.
Onset of action	2 hours[2][3]
Biological half-life	≤1 hour (prodrug molecule) 9–11 hours (dextroamphetamine)
Duration of action	12 hours[2][3]
Excretion	Renal: ~2%
Identifiers
IUPAC name[show]
Synonyms	Vyvanse
CAS Number	608137-32-2 [IUPHAR]
PubChem CID	11597698
IUPHAR/BPS	7213
DrugBank	DB01255
ChemSpider	9772458
UNII	H645GUL8KJ
ChEMBL	CHEMBL1201222
Chemical and physical data
Formula	C15H25N3O
Molar mass	263.378 g/mol
3D model (Jmol)	Interactive image

////////

CC(CC1=CC=CC=C1)NC(=O)C(CCCCN)N

LOXO-195
CAS: 2097002-61-2
Chemical Formula: C20H21FN6O

Molecular Weight: 380.4274

2097002-59-8 (RS-isomer)   1350884-56-8 (R racemic)

Synonym: LOXO-195; LOXO 195; LOXO195.

IUPAC: (13E,14E,22R,6R)-35-fluoro-6-methyl-7-aza-1(5,3)-pyrazolo[1,5-a]pyrimidina-3(3,2)-pyridina-2(1,2)-pyrrolidinacyclooctaphan-8-one

10H-5,7-Ethenopyrazolo[3,4-d]pyrido[2,3-k]pyrrolo[2,1-m][1,3,7]triazacyclotridecin-10-one, 17-fluoro-1,2,3,11,12,13,14,18b-octahydro-12-methyl-, (12R,18bR)-

SMILES Code: FC1=CN=C(CC[C@@H](C)NC(C2=C3N(C=CC4=N3)N=C2)=O)C([C@@H]5N4CCC5)=C1

LOXO-195 is a potent and selective TRK inhibitor capable of addressing potential mechanisms of acquired resistance that may emerge in patients receiving larotrectinib (LOXO-101) or multikinase inhibitors with anti-TRK activity. LOXO-195 demonstrated potent inhibition of TRK fusions, including critical acquired resistance mutations, in enzyme and cellular assays, with minimal activity against other kinases. In diverse TRK fusion mouse models, LOXO-195 inhibited phospho-ERK and caused dramatic tumor growth inhibition, superior to first generation TRK inhibitors, without significant toxicity.

Tropomyosin-related kinase (TRK) is a receptor tyrosine kinase family of

neurotrophin receptors that are found in multiple tissues types. Three members of the TRK proto-oncogene family have been described: TrkA, TrkB, and TrkC, encoded by the NTRKI, NTRK2, and NTRK3 genes, respectively. The TRK receptor family is involved in neuronal development, including the growth and function of neuronal synapses, memory

development, and maintenance, and the protection of neurons after ischemia or other types of injury (Nakagawara, Cancer Lett. 169: 107-114, 2001).

TRK was originally identified from a colorectal cancer cell line as an oncogene fusion containing 5′ sequences from tropomyosin-3 (TPM3) gene and the kinase domain encoded by the 3′ region of the neurotrophic tyrosine kinase, receptor, type 1 gene (NTRKI) (Pulciani et al., Nature 300:539-542, 1982; Martin-Zanca et al., Nature 319:743-748, 1986). TRK gene fusions follow the well-established paradigm of other oncogenic fusions, such as those involving ALK and ROSl, which have been shown to drive the growth of tumors and can be successfully inhibited in the clinic by targeted drugs (Shaw et al., New Engl. J. Med. 371 : 1963-1971, 2014; Shaw et al., New Engl. J. Med. 370: 1189-1197, 2014). Oncogenic TRK fusions induce cancer cell proliferation and engage critical cancer-related downstream signaling pathways such as mitogen activated protein kinase (MAPK) and AKT (Vaishnavi et al., Cancer Discov. 5:25-34, 2015). Numerous oncogenic rearrangements involving

NTRK1 and its related TRK family members NTRK2 and NTRK3 have been described (Vaishnavi et al., Cancer Disc. 5:25-34, 2015; Vaishnavi et al., Nature Med. 19: 1469-1472, 2013). Although there are numerous different 5′ gene fusion partners identified, all share an in-frame, intact TRK kinase domain. A variety of different Trk inhibitors have been developed to treat cancer (see, e.g., U.S. Patent Application Publication No. 62/080,374,

International Application Publication Nos. WO 11/006074, WO 11/146336, WO 10/033941, and WO 10/048314, and U.S. Patent Nos. 8,933,084, 8,791, 123, 8,637,516, 8,513,263, 8,450,322, 7,615,383, 7,384,632, 6, 153,189, 6,027,927, 6,025,166, 5,910,574, 5,877,016, and 5,844,092).

1H NMR PREDICT

13C NMR PREDICT

WO 2017075107

Can·cer, redefined
Lisa M. Jarvis
C&EN Global Enterp, 2017, 95 (27), pp 26–30
Publication Date (Web): July 3, 2017 (Article)
DOI: 10.1021/cen-09527-cover

http://pubs.acs.org/doi/full/10.1021/cen-09527-cover

Lisa M. JarvisC&EN, 2017, 95 (27), pp 26–30July 3, 2017

When Adrienne Skinner was diagnosed with ampullary cancer, a rare gastrointestinal tumor, in early 2013, it didn’t come as a complete surprise. For nearly a decade, she had known her genes were not in her favor. What she didn’t know was that her genes would also point the way to a cure. Skinner has Lynch syndrome, an inherited disorder caused by a defect in mismatch repair (MMR) genes, which encode for proteins that spot and fix mistakes occurring during DNA replication. People with Lynch syndrome have an up to 70% risk of developing colon cancer. Women with the disorder have similarly high chances of developing endometrial cancer at an early age. The first time Skinner heard about the syndrome was in late 2004, after her sister was diagnosed with colon, ovarian, and endometrial cancers, the telltale trifecta associated with Lynch syndrome. It turned out that Skinner, her sister, and their

• A Next-Generation TRK Kinase Inhibitor Overcomes Acquired Resistance to Prior TRK Kinase Inhibition in Patients with TRK Fusion-Positive Solid Tumors
• Clinical Safety and Activity from a Phase 1 Study of LOXO-101, a Selective TRKA/B/C Inhibitor, in Solid Tumor Patients with NTRK Gene Fusions
• The Development of LOXO-195, a Second Generation TRK Kinase Inhibitor that Overcomes Acquired Resistance to First Generation Inhibitors in Patients with TRK-Fusion Cancers
• Acquired Resistance to the TRK Inhibitor Entrectinib in Colorectal Cancer
• What Hides Behind the MASC: Clinical Response and Acquired Resistance to Entrectinib After ETV6-NTRK3 Identification in a Mammary Analogue Secretory Carcinoma (MASC)

/////////LOXO 195, 2097002-61-2

Voxilaprevir

• Molecular FormulaC₄₀H₅₂F₄N₆O₉S
• Average mass868.934 Da

Voxilaprevir is a hepatitis C virus (HCV) nonstructural (NS) protein 3/4A protease inhibitor that is used in combination with sofosbuvirand velpatasvir. The combination has the trade name Vosevi and has received a positive opinion from the European Committee for Medicinal Products for Human Use in June 2017.^[1]

In July 18, 2017, Vosevi was approved by Food and drug administration.^[2]

The hepatitis C virus (HCV), a member of the hepacivirus genera within the Flaviviridae family, is the leading cause of chronic liver disease worldwide (Boyer, N. et al. J Hepatol. 2000, 32, 98-1 12). Consequently, a significant focus of current antiviral research is directed toward the development of improved methods for the treatment of chronic HCV infections in humans (Ciesek, S., von Hahn T., and Manns, MP., Clin. Liver Dis., 201 1 , 15, 597-609; Soriano, V. et al, J. Antimicrob. Chemother., 201 1 , 66, 1573-1686; Brody, H., Nature Outlook, 201 1 , 474, S1 -S7; Gordon, C. P., et al., J. Med. Chem. 2005, 48, 1 -20;

Maradpour, D., et al., Nat. Rev. Micro. 2007, 5, 453-463).

Virologic cures of patients with chronic HCV infection are difficult to achieve because of the prodigious amount of daily virus production in chronically infected patients and the high spontaneous mutability of HCV (Neumann, et al., Science 1998, 282, 103-7; Fukimoto, et al., Hepatology, 1996, 24, 1351 -4;

Domingo, et al., Gene 1985, 40, 1 -8; Martell, et al., J. Virol. 1992, 66, 3225-9). HCV treatment is further complicated by the fact that HCV is genetically diverse and expressed as several different genotypes and numerous subtypes. For example, HCV is currently classified into six major genotypes (designated 1 -6), many subtypes (designated a, b, c, and so on), and about 100 different strains (numbered 1 , 2, 3, and so on).

HCV is distributed worldwide with genotypes 1 , 2, and 3 predominate within the United States, Europe, Australia, and East Asia (Japan, Taiwan, Thailand, and China). Genotype 4 is largely found in the Middle East, Egypt and central Africa while genotype 5 and 6 are found predominantly in South Africa and South East Asia respectively (Simmonds, P. et al. J Virol. 84: 4597-4610, 2010).

The combination of ribavirin, a nucleoside analog, and interferon-alpha (a) (IFN), is utilized for the treatment of multiple genotypes of chronic HCV infections in humans. However, the variable clinical response observed within patients and the toxicity of this regimen have limited its usefulness. Addition of a HCV protease inhibitor (telaprevir or boceprevir) to the ribavirin and IFN regimen improves 12-week post-treatment virological response (SVR12) rates

substantially. However, the regimen is currently only approved for genotype 1 patients and toxicity and other side effects remain.

The use of directing acting antivirals to treat multiple genotypes of HCV infection has proven challenging due to the variable activity of antivirals against the different genotypes. HCV protease inhibitors frequently have compromised in vitro activity against HCV genotypes 2 and 3 compared to genotype 1 (See, e.g., Table 1 of Summa, V. et al., Antimicrobial Agents and Chemotherapy, 2012, 56, 4161 -4167; Gottwein, J. et al, Gastroenterology, 201 1 , 141 , 1067-1079).

Correspondingly, clinical efficacy has also proven highly variable across HCV genotypes. For example, therapies that are highly effective against HCV genotype 1 and 2 may have limited or no clinical efficacy against genotype 3.

(Moreno, C. et al., Poster 895, 61 ^st AASLD Meeting, Boston, MA, USA, Oct. 29 – Nov. 2, 2010; Graham, F., et al, Gastroenterology, 201 1 , 141 , 881 -889; Foster, G.R. et al., EASL 45^th Annual Meeting, April 14-18, 2010, Vienna, Austria.) In some cases, antiviral agents have good clinical efficacy against genotype 1 , but lower and more variable against genotypes 2 and 3. (Reiser, M. et al.,

Hepatology, 2005, 41 ,832-835.) To overcome the reduced efficacy in genotype 3 patients, substantially higher doses of antiviral agents may be required to achieve substantial viral load reductions (Fraser, IP et al., Abstract #48, HEP DART 201 1 , Koloa, HI, December 201 1 .)

Antiviral agents that are less susceptible to viral resistance are also needed. For example, resistance mutations at positions 155 and 168 in the HCV protease frequently cause a substantial decrease in antiviral efficacy of HCV protease inhibitors (Mani, N. Ann Forum Collab HIV Res., 2012, 14, 1 -8;

Romano, KP et al, PNAS, 2010, 107, 20986-20991 ; Lenz O, Antimicrobial agents and chemotherapy, 2010, 54,1878-1887.)

In view of the limitations of current HCV therapy, there is a need to develop more effective anti-HCV therapies. It would also be useful to provide therapies that are effective against multiple HCV genotypes and subtypes.

Kyla Ramey (Bjornson)

Senior CTM Associate at Gilead Sciences

……………………………………………………………………………….

PATENT

WO 2014008285

https://www.google.com/patents/WO2014008285A1?cl=en

RELATIVE SIMILAR EXAMPLE WITHOUT DIFLUORO GROUPS, BUT NOT SAME COMPD

Example 1. Preparation of (1 aR,5S,8S,9S,10R,22aR)-5-tert-butyl-N- [(1 R,2R)-2-(difluoromethyl)-1 -{[(1 – methylcyclopropyl)sulfonyl]carbamoyl}cyclopropyl]-9-ethyl-14-methoxy-3,6-dioxo- 1 ,1 a,3,4,5,6,9,10,18,19,20,21 ,22,22a-tetradecahydro-8H-7,10- methanocyclopropa[18,19][1 ,10,3,6]dioxadiazacyclononadecino[1 1 ,12- b]quinoxaline-8-carboxamide.

Step 1 . Preparation of 1-1 : A mixture containing Intermediate B4 (2.03 g, 6.44 mmol), Intermediate E1 (1 .6 g, 5.85 mmol), and cesium carbonate (3.15 g, 9.66 mmol) in MeCN (40 mL) was stirred vigorously at rt under an atmosphere of Ar for 16 h. The reaction was then filtered through a pad of Celite and the filtrate concentrated in vacuo. The crude material was purified by silica gel

chromatography to provide 1-1 as a white solid (2.5 g). LCMS-ESI⁺ (m/z): [M- Boc+2H]⁺ calcd for C₂oH27CIN₃O₄: 408.9; found: 408.6.

Step 2. Preparation of 1-2: To a solution 1 -1 (2.5 g, 4.92 mmol) in dioxane

(10 mL) was added hydrochloric acid in dioxane (4 M, 25 mL, 98.4 mmol) and the reaction stirred at rt for 5 h. The crude reaction was concentrated in vacuo to give 1-2 as a white solid (2.49 g) that was used in subsequently without further purification. LCMS-ESI⁺ (m/z): [M]⁺ calcd for C₂oH₂6CIN₃O₄: 407.9; found: 407.9.

Step 3. Preparation of 1-3: To a DMF (35 mL) solution of 1-2 (2.49 g, 5.61 mmol), Intermediate D1 (1 .75 mg, 6.17 mmol) and DIPEA (3.9 mL, 22.44 mmol) was added COMU (3.12 g, 7.29 mmol) and the reaction was stirred at rt for 3 h. The reaction was quenched with 5% aqueous citric acid solution and extracted with EtOAc, washed subsequently with brine, dried over anhydrous MgSO , filtered and concentrated to produce 1 -3 as an orange foam (2.31 g) that was used without further purification. LCMS-ESI⁺ (m/z): [M]⁺ calcd for C3₅H₄9CIN₄O₇: 673.3; found: 673.7.

Step 4. Preparation of 1-4: To a solution of 1-3 (2.31 g, 3.43 mmol), TEA (0.72 mL, 5.15 mmol) and potassium vinyltrifluoroborate (0.69 mg, 5.15 mmol) in EtOH (35 mL) was added PdCI₂(dppf) (0.25 g, 0.34 mmol, Frontier Scientific). The reaction was sparged with Argon for 15 min and heated to 80 °C for 2 h. The reaction was adsorbed directly onto silica gel and purified using silica gel chromatography to give 1 -4 as a yellow oil (1 .95 g). LCMS-ESI⁺ (m/z): [M+H]⁺ calcd for C₃7H₅3N₄O₇: 665.4; found: 665.3.

Step 5. Preparation of 1 -5: To a solution of 1 -4 (1 .95 g, 2.93 mmol) in

DCE (585 ml_) was added Zhan 1 B catalyst (0.215 g, 0.29 mmol, Strem) and the reaction was sparged with Ar for 15 min. The reaction was heated to 80 °C for 1 .5 h, allowed to cool to rt and concentrated. The crude product was purified by silica gel chromatography to produce 1 -5 as a yellow oil (1 .47 g; LCMS-ESI⁺ (m/z): [M+H]⁺ calcd for C₃5H₄₉N₄O₇: 637.4; found: 637.3).

Step 6. Preparation of 1 -6: A solution of 1 -5 (0.97 g, 1 .52 mmol) in EtOH (15 ml_) was treated with Pd/C (10 wt % Pd, 0.162 g). The atmosphere was replaced with hydrogen and stirred at rt for 2 h. The reaction was filtered through Celite, the pad washed with EtOAc and concentrated to give 1 -6 as a brown foamy solid (0.803 g) that was used subsequently without further purification. LCMS-ESr (m/z): [M+H]⁺ calcd for C₃5H₅i N₄O₇: 639.4; found: 639.3.

Step 7. Preparation of 1 -7: To a solution of 1 -6 (0.803 g, 1 .26 mmol) in DCM (10 ml_) was added TFA (5 ml_) and stirred at rt for 3 h. An additional 2 ml_ TFA was added and the reaction stirred for another 1 .5 h. The reaction was concentrated to a brown oil that was taken up in EtOAc (35 ml_). The organic solution was washed with water. After separation of the layers, sat. aqueous NaHCO3 was added with stirring until the aqueous layer reached a pH ~ 7-8. The layers were separated again and the aqueous extracted with EtOAc twice. The combined organics were washed with 1 M aqueous citric acid, brine, dried over anhydrous MgSO₄, filtered and concentrated to produce 1 -6 as a brown foamy solid (0.719 g) that was used subsequently without further purification. LCMS-ESr (m/z): [M+H]⁺ calcd for C₃i H₄₃N₄O₇: 583.3; found: 583.4 .

Step 8. Preparation of Example 1 : To a solution of 1 -7 (0.200 g, 0.343 mmol), Intermediate A10 (0.157 g, 0.515 mmol), DMAP (0.063 g, 0.51 mmol) and DIPEA (0.3 ml_, 1 .72 mmol) in DMF (3 ml_) was added HATU (0.235 g, 0.617 mmol) and the reaction was stirred at rt o/n. The reaction was diluted with MeCN and purified directly by reverse phase HPLC (Gemini, 30-100% MeCN/H₂O + 0.1 % TFA) and lyophilized to give Example 1 (1 18.6 mg) as a solid TFA salt. Analytic HPLC RetTime: 8.63 min. LCMS-ESI⁺ (m/z): [M+H]⁺ calcd for

C₄₀H55F₂N₆O9S: 833.4; found: 833.5. ¹H NMR (400 MHz, CD₃OD) δ 9.19 (s, 1 H); 7.80 (d, J = 8.8 Hz, 1 H); 7.23 (dd, J = 8.8, 2.4 Hz, 1 H); 7.15 (d, J = 2.4 Hz, 1 H); 5.89 (d, J = 3.6 Hz, 1 H); 5.83 (td, J_H-F = 55.6 Hz, J = 6.4 Hz, 1 H); 4.56 (d, J = 7.2 Hz, 1 H); 4.40 (s, 1 H) 4.38 (ap d, J = 7.2 Hz, 1 H); 4.16 (dd, J = 12, 4 Hz, 1 H); 3.93 (s, 3H); 3.75 (dt, J = 7.2, 4 Hz, 1 H); 3.00-2.91 (m, 1 H); 2.81 (td, J = 12, 4.4 Hz, 1 H); 2.63-2.54 (m, 1 H); 2.01 (br s, 2H); 1 .88-1 .64 (m, 3H); 1 .66-1 .33 (m, 1 1 H) 1 .52 (s, 3H); 1 .24 (t, J = 7.2 Hz, 3H); 1 .10 (s, 9H); 1 .02-0.96 (m, 2H); 0.96- 0.88 (m, 2H); 0.78-0.68 (m, 1 H); 0.55-0.46 (m, 1 H).

PATENT

US 20150175625

PATENT

US 20150175626

https://patentscope.wipo.int/search/en/detail.jsf;jsessionid=C6BE27513351D0F12E95BC8C04756872.wapp1nA?docId=WO2015100145&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription

The hepatitis C virus (HCV), a member of the hepacivirus genera within the Flaviviridae family, is the leading cause of chronic liver disease worldwide (Boyer, N. et al. J Hepatol. 2000, 32, 98-112). Consequently, a significant focus of current antiviral research is directed toward the development of improved methods for the treatment of chronic HCV infections in humans (Ciesek, S., von Hahn T., and Manns, MP., Clin. Liver Dis., 2011, 15, 597-609; Soriano, V. et al, J. Antimicrob. Chemother., 2011, 66, 1573-1686; Brody, H., Nature Outlook, 2011, 474, S1-S7; Gordon, C. P., et al, J. Med. Chem. 2005, 48, 1-20; Maradpour, D., et al, Nat. Rev. Micro. 2007, 5, 453-463).

Virologic cures of patients with chronic HCV infection are difficult to achieve because of the prodigious amount of daily virus production in chronically infected patients and the high spontaneous mutability of HCV (Neumann, et al, Science 1998, 282, 103-7; Fukimoto, et al, Hepatology, 1996, 24, 1351-4; Domingo, et al, Gene 1985, 40, 1-8; Martell, et al, J. Virol. 1992, 66, 3225-9). HCV treatment is further complicated by the fact that HCV is genetically diverse and expressed as several different genotypes and numerous subtypes. For example, HCV is currently classified into six major genotypes (designated 1-6), many subtypes (designated a, b, c, and so on), and about 100 different strains (numbered 1, 2, 3, and so on).

HCV is distributed worldwide with genotypes 1, 2, and 3 predominate within the United States, Europe, Australia, and East Asia (Japan, Taiwan, Thailand, and China). Genotype 4 is largely found in the Middle East, Egypt and central Africa while genotype 5 and 6 are found predominantly in South Africa and South East Asia respectively (Simmonds, P. et al. J Virol. 84: [0006] There remains a need to develop effective treatments for HCV infections. Suitable compounds for the treatment of HCV infections are disclosed in U.S. Publication No. 2014-0017198, titled “Inhibitors of Hepatitis C Virus” filed on July 2, 2013 including the compound of formula I:

Example 1. Synthesis of (laR,5S,8S,9S,10R,22aR)-5-teri-butyl- V-[(lR,2R)-2-(difluoromethyl)- 1-{ [(1-methylcyclopr opyl)sulfonyl] carbamoyl} cyclopropyl] -9-ethyl- 18,18- difluoro-14-methoxy-3,6-dioxo-l,la,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19] [1,10,3,6] dioxadiazacyclononadecino[ll,12-6]quinoxaline-8- carboxamide (I) by route I

[0195] Compound of formula I was synthesized via route I as shown below:

Synthesis of intermediates for compound of formula I SEE PATENT

US  20150175626

References

Voxilaprevir

Clinical data
Trade names	Vosevi (combination with sofosbuvir and velpatasvir)
Identifiers
IUPAC name[show]
CAS Number	1535212-07-7
PubChemCID	89921642
ChemSpider	44209500
UNII	0570F37359
Chemical and physical data
Formula	C40H52F4N6O9S
Molar mass	868.94 g·mol−1

FDA approves Vosevi for Hepatitis C

//////////Voxilaprevir, فوكسيلابريفير ,  伏西瑞韦 , Воксилапревир , fda 2017, GS 9857, gilead, 1535212-07-7

CAS: 1622848-92-3 (free base),  1987858-31-0 (hydrate)

Chemical Formula: C20H19N5O3

Molecular Weight: 377.404

5-Benzyl-N-[(3S)-5-methyl-4-oxo-2,3,4,5-tetrahydro-1,5-benzoxazepin-3-yl]-4H-1,2,4-triazole-3-carboxamide

(S)-5-benzyl-N-(5-methyl-4-oxo-2,3,4,5-tetrahydrobenzo[b][l,4]oxazepin-3-yl)-4H-l,2,4- triazole-3-carboxamide

• 3-(Phenylmethyl)-N-[(3S)-2,3,4,5-tetrahydro-5-methyl-4-oxo-1,5-benzoxazepin-3-yl]-1H-1,2,4-triazole-5-carboxamide
• (S)-5-Benzyl-N-(5-methyl-4-oxo-2,3,4,5-tetrahydrobenzo[b][1,4]oxazepin-3-yl)-4H-1,2,4-triazole-3-carboxamide

GSK2982772 is a potent and selective receptor Interacting Protein 1 (RIP1) Kinase Specific Clinical Candidate for the Treatment of Inflammatory Diseases. GSK2982772 is, currently in phase 2a clinical studies for psoriasis, rheumatoid arthritis, and ulcerative colitis. GSK2982772 potently binds to RIP1 with exquisite kinase specificity and has excellent activity in blocking many TNF-dependent cellular responses. RIP1 has emerged as an important upstream kinase that has been shown to regulate inflammation through both scaffolding and kinase specific functions.

GSK-2982772, an oral receptor-interacting protein-1 (RIP1) kinase inhibitor, is in phase II clinical development at GlaxoSmithKline for the treatment of active plaque-type psoriasis, moderate to severe rheumatoid arthritis, and active ulcerative colitis. A phase I trial was also completed for the treatment of inflammatory bowel disease using capsule and solution formulations.

• Originator GlaxoSmithKline
• Class Antipsoriatics
• Mechanism of Action Receptor-interacting protein serine-threonine kinase inhibitors

Highest Development Phases

• Phase II Plaque psoriasis; Rheumatoid arthritis; Ulcerative colitis
• Phase I Inflammatory bowel diseases

Most Recent Events

• 15 Dec 2016 Biomarkers information updated
• 01 Nov 2016 Phase-II clinical trials in Ulcerative colitis (Adjunctive treatment) in USA (PO) (NCT02903966)
• 01 Oct 2016 Phase-II clinical trials in Rheumatoid arthritis in Poland (PO) (NCT02858492)

PHASE 2 Psoriasis, plaque GSK

Deepak BANDYOPADHYAY

Data Science and Informatics Leader | Innovation Advocate

He is  a data scientist and innovator with experience in both early and late stages of drug development. his current role involves the late stage of drug product development. I’m leading a project to bring GSK’s large molecule process and analytical data onto our big data platform and develop new data analysis and modeling capabilities. Also, working within GSK’s Advanced Manufacturing Technology (AMT) initiative provides plenty of other opportunities to impact how we make medicines.

Previously as a computational chemist (i.e. a data scientist in drug discovery), he worked with scientists from many domains, including chemists, biologists, and other informaticians. he enjoys digging into all the computational aspects of life science research, and solving data challenges by exploiting adjacencies and connections – between diverse fields of knowledge, and the equally diverse scientists trained in them. 

He has supported multiple drug discovery projects at GSK starting from target identification (“how should we modulate disease X?”) through to candidate selection and early clinical development (“let’s see if what we discovered can become a medicine”). Deriving insight by custom data integration is one of my specialties; recently he designed and implemented a platform for integrating data sets from multiple experiments that will be used by GSK screening scientists to find and combine hits. 

A trained computer scientist and cheminformatician, he is  an active member of the algorithms, data science and internal innovation communities at GSK, leading many of these efforts. 

His Ph.D. work introduced new computational geometry techniques for structural bioinformatics and protein function prediction. I have touched on several other subject areas:

* data mining/machine learning (predictive modeling and graph mining), 
* computer graphics and augmented reality (one of the pioneers of projection mapping)
* robotics (keen current interest and future aspiration)

Receptor-interacting protein- 1 (RIP1) kinase, originally referred to as RIP, is a TKL family serine/threonine protein kinase involved in innate immune signaling. RIPl kinase is a RHIM domain containing protein, with an N-terminal kinase domain and a C-terminal death domain ((2005) Trends Biochem. Sci. 30, 151-159). The death domain of RIPl mediates interaction with other death domain containing proteins including Fas and TNFR-1 ((1995) Cell 81 513-523), TRAIL-Rl and TRAIL-R2 ((1997) Immunity 7, 821-830) and TRADD ((1996) Immunity 4, 387-396), while the RHIM domain is crucial for binding other RHFM domain containing proteins such as TRIF ((2004) Nat Immunol. 5, 503-507), DAI ((2009) EMBO Rep. 10, 916-922) and RIP3 ((1999) J. Biol. Chem. 274, 16871-16875); (1999) Curr. Biol. 9, 539-542) and exerts many of its effects through these interactions. RIPl is a central regulator of cell signaling, and is involved in mediating both pro-survival and programmed cell death pathways which will be discussed below.

The role for RIPl in cell signaling has been assessed under various conditions

[including TLR3 ((2004) Nat Immunol. 5, 503-507), TLR4 ((2005) J. Biol. Chem. 280,

36560-36566), TRAIL ((2012) J .Virol. Epub, ahead of print), FAS ((2004) J. Biol. Chem. 279, 7925-7933)], but is best understood in the context of mediating signals downstream of the death receptor TNFRl ((2003) Cell 114, 181-190). Engagement of the TNFR by TNF leads to its oligomerization, and the recruitment of multiple proteins, including linear K63-linked polyubiquitinated RIPl ((2006) Mol. Cell 22, 245-257), TRAF2/5 ((2010) J. Mol. Biol. 396, 528-539), TRADD ((2008) Nat. Immunol. 9, 1037-1046) and cIAPs ((2008) Proc. Natl. Acad. Sci. USA. 105, 1 1778-11783), to the cytoplasmic tail of the receptor. This complex which is dependent on RIPl as a scaffolding protein (i.e. kinase

independent), termed complex I, provides a platform for pro-survival signaling through the activation of the NFKB and MAP kinases pathways ((2010) Sci. Signal. 115, re4).

Alternatively, binding of TNF to its receptor under conditions promoting the

deubiquitination of RIPl (by proteins such as A20 and CYLD or inhibition of the cIAPs) results in receptor internalization and the formation of complex II or DISC (death-inducing signaling complex) ((2011) Cell Death Dis. 2, e230). Formation of the DISC, which contains RIPl, TRADD, FADD and caspase 8, results in the activation of caspase 8 and the onset of programmed apoptotic cell death also in a RIPl kinase independent fashion ((2012) FEBS J 278, 877-887). Apoptosis is largely a quiescent form of cell death, and is involved in routine processes such as development and cellular homeostasis.

Under conditions where the DISC forms and RJP3 is expressed, but apoptosis is inhibited (such as FADD/caspase 8 deletion, caspase inhibition or viral infection), a third RIPl kinase-dependent possibility exists. RIP3 can now enter this complex, become phosphorylated by RIPl and initiate a caspase-independent programmed necrotic cell death through the activation of MLKL and PGAM5 ((2012) Cell 148, 213-227); ((2012) Cell 148, 228-243); ((2012) Proc. Natl. Acad. Sci. USA. 109, 5322-5327). As opposed to apoptosis, programmed necrosis (not to be confused with passive necrosis which is not programmed) results in the release of danger associated molecular patterns (DAMPs) from the cell.

These DAMPs are capable of providing a “danger signal” to surrounding cells and tissues, eliciting proinflammatory responses including inflammasome activation, cytokine production and cellular recruitment ((2008 Nat. Rev. Immunol 8, 279-289).

Dysregulation of RIPl kinase-mediated programmed cell death has been linked to various inflammatory diseases, as demonstrated by use of the RIP3 knockout mouse (where RIPl -mediated programmed necrosis is completely blocked) and by Necrostatin-1 (a tool inhibitor of RIPl kinase activity with poor oral bioavailability). The RIP3 knockout mouse has been shown to be protective in inflammatory bowel disease (including Ulcerative colitis and Crohn’s disease) ((2011) Nature 477, 330-334), Psoriasis ((2011) Immunity 35, 572-582), retinal-detachment-induced photoreceptor necrosis ((2010) PNAS 107, 21695-21700), retinitis pigmentosa ((2012) Proc. Natl. Acad. Sci., 109:36, 14598-14603), cerulein-induced acute pancreatits ((2009) Cell 137, 1100-1111) and Sepsis/systemic inflammatory response syndrome (SIRS) ((2011) Immunity 35, 908-918). Necrostatin-1 has been shown to be effective in alleviating ischemic brain injury ((2005) Nat. Chem. Biol. 1, 112-119), retinal ischemia/reperfusion injury ((2010) J. Neurosci. Res. 88, 1569-1576), Huntington’s disease ((2011) Cell Death Dis. 2 el 15), renal ischemia reperfusion injury ((2012) Kidney Int. 81, 751-761), cisplatin induced kidney injury ((2012) Ren. Fail. 34, 373-377) and traumatic brain injury ((2012) Neurochem. Res. 37, 1849-1858). Other diseases or disorders regulated at least in part by RIPl -dependent apoptosis, necrosis or cytokine production include hematological and solid organ malignancies ((2013) Genes

Dev. 27: 1640-1649), bacterial infections and viral infections ((2014) Cell Host & Microbe 15, 23-35) (including, but not limited to, tuberculosis and influenza ((2013) Cell 153, 1-14)) and Lysosomal storage diseases (particularly, Gaucher Disease, Nature Medicine Advance Online Publication, 19 January 2014, doi: 10.1038/nm.3449).

A potent, selective, small molecule inhibitor of RIP1 kinase activity would block RIP 1 -dependent cellular necrosis and thereby provide a therapeutic benefit in diseases or events associated with DAMPs, cell death, and/or inflammation.

Patent

WO 2014125444

Example 12

Method H

(S)-5-benzyl-N-(5-methyl-4-oxo-2,3,4,5-tetrahydrobenzo[b][l,4]oxazepin-3-yl)-4H-l,2,4- triazole-3-carboxamide

A mixture of (S)-3-amino-5-methyl-2,3-dihydrobenzo[b][l,4]oxazepin-4(5H)-one, hydrochloride (4.00 g, 16.97 mmol), 5-benzyl-4H-l,2,4-triazole-3-carboxylic acid, hydrochloride (4.97 g, 18.66 mmol) and DIEA (10.37 mL, 59.4 mmol) in isopropanol (150 mL) was stirred vigorously for 10 minutes and then 2,4,6-tripropyl-l,3,5,2,4,6-trioxatriphosphinane 2,4,6-trioxide (T3P) (50% by wt. in EtOAc) (15.15 mL, 25.5 mmol) was added. The mixture was stirred at rt for 10 minutes and then quenched with water and concentrated to remove isopropanol. The resulting crude material is dissolved in EtOAc and washed with 1M HC1, satd. NaHC0₃ and brine. Organics were concentrated and purified by column chromatography (220 g silica column; 20-90% EtOAc/hexanes, 15 min.; 90%, 15 min.) to give the title compound as a light orange foam (5.37 g, 83%). 1H NMR (MeOH-d₄) δ: 7.40 – 7.45 (m, 1H), 7.21 – 7.35 (m, 8H), 5.01 (dd, J = 11.6, 7.6 Hz, 1H), 4.60 (dd, J = 9.9, 7.6 Hz, 1H), 4.41 (dd, J = 11.4, 9.9 Hz, 1H), 4.17 (s, 2H), 3.41 (s, 3H); MS (m/z) 378.3 (M+H⁺).

Alternative Preparation:

To a solution of (S)-3-amino-5-methyl-2,3-dihydrobenzo[b][l,4]oxazepin-4(5H)-one hydrochloride (100 g, 437 mmol), 5-benzyl-4H-l,2,4-triazole-3-carboxylic acid hydrochloride (110 g, 459 mmol) in DCM (2.5 L) was added DIPEA (0.267 L, 1531 mmol) at 15 °C. The reaction mixture was stirred for 10 min. and 2,4,6-tripropyl-l, 3, 5,2,4,6-trioxatriphosphinane 2,4,6-trioxide >50 wt. % in ethyl acetate (0.390 L, 656 mmol) was slowly added at 15 °C. After stirring for 60 mins at RT the LCMS showed the reaction was complete, upon which time it was quenched with water, partitioned between DCM and washed with 0.5N HCl aq (2 L), saturated aqueous NaHC0₃ (2 L), brine (2 L) and water (2 L). The organic phase was separated and activated charcoal (100 g) and sodium sulfate

(200 g) were added. The dark solution was shaken for 1 h before filtering. The filtrate was then concentrated under reduced pressure to afford the product as a tan foam (120 g). The product was dried under a high vacuum at 50 °C for 16 h. 1H MR showed 4-5% wt of ethyl acetate present. The sample was dissolved in EtOH (650 ml) and stirred for 30 mins, after which the solvent was removed using a rotavapor (water-bath T=45 °C). The product was dried under high vacuum for 16 h at RT (118 g, 72% yield). The product was further dried under high vacuum at 50 °C for 5 h. 1H NMR showed <1% of EtOH and no ethyl acetate. 1H NMR (400 MHz, DMSO-i¾) δ ppm 4.12 (s, 2 H), 4.31 – 4.51 (m, 1 H), 4.60 (t, J=10.36 Hz, 1 H), 4.83 (dt, 7=11.31, 7.86 Hz, 1 H), 7.12 – 7.42 (m, 8 H), 7.42 – 7.65 (m, 1 H), 8.45 (br. s., 1 H), 14.41 (br. s., 1 H). MS (m/z) 378 (M + H⁺).

Crystallization:

(S)-5-Benzyl-N-(5-methyl-4-oxo-2,3,4,5-tetrahydrobenzo[b][l,4]oxazepin-3-yl)-4H-l,2,4-triazole-3-carboxamide (100 mg) was dissolved in 0.9 mL of toluene and 0.1 mL of methylcyclohexane at 60 °C, then stirred briskly at room temperature (20 °C) for 4 days. After 4 days, an off-white solid was recovered (76 mg, 76% recovery). The powder X-ray diffraction (PXRD) pattern of this material is shown in Figure 7 and the corresponding diffraction data is provided in Table 1.

The PXRD analysis was conducted using a PANanalytical X’Pert Pro

diffractometer equipped with a copper anode X-ray tube, programmable slits, and

X’Celerator detector fitted with a nickel filter. Generator tension and current were set to 45kV and 40mA respectively to generate the copper Ka radiation powder diffraction pattern over the range of 2 – 40°2Θ. The test specimen was lightly triturated using an agate mortar and pestle and the resulting fine powder was mounted onto a silicon background plate.

Table 1.

Paper

Discovery of a first-in-class receptor interacting protein 1 (RIP1) kinase specific clinical candidate (GSK2982772) for the treatment of inflammatory diseases
J Med Chem 2017, 60(4): 1247

http://pubs.acs.org/doi/pdf/10.1021/acs.jmedchem.6b01751

RIP1 regulates necroptosis and inflammation and may play an important role in contributing to a variety of human pathologies, including immune-mediated inflammatory diseases. Small-molecule inhibitors of RIP1 kinase that are suitable for advancement into the clinic have yet to be described. Herein, we report our lead optimization of a benzoxazepinone hit from a DNA-encoded library and the discovery and profile of clinical candidate GSK2982772 (compound 5), currently in phase 2a clinical studies for psoriasis, rheumatoid arthritis, and ulcerative colitis. Compound 5 potently binds to RIP1 with exquisite kinase specificity and has excellent activity in blocking many TNF-dependent cellular responses. Highlighting its potential as a novel anti-inflammatory agent, the inhibitor was also able to reduce spontaneous production of cytokines from human ulcerative colitis explants. The highly favorable physicochemical and ADMET properties of 5, combined with high potency, led to a predicted low oral dose in humans.

J. Med. Chem. 2017, 60, 1247−1261

(S)-5-Benzyl-N-(5-methyl-4-oxo-2,3,4,5-tetrahydrobenzo[b]- [1,4]oxazepin-3-yl)-4H-1,2,4-triazole-3-carboxamide (5).

EtOAc solvate. 1 H NMR (DMSO-d6) δ ppm 14.41 (br s, 1 H), 8.48 (br s, 1 H), 7.50 (dd, J = 7.7, 1.9 Hz, 1 H), 7.12−7.40 (m, 8 H), 4.83 (dt, J = 11.6, 7.9 Hz, 1 H), 4.60 (t, J = 10.7 Hz, 1 H), 4.41 (dd, J = 9.9, 7.8 Hz, 1 H), 4.12 (s, 2 H), 3.31 (s, 3 H). Anal. Calcd for C20H20N5O3·0.026EtOAc·0.4H2O C, 62.36; H, 5.17; N, 18.09. Found: C, 62.12; H, 5.05; N, 18.04.

Synthesis of (<it>S</it>)-3-amino-benzo[<it>b</it>][1,4]oxazepin-4-one via Mitsunobu and S<INF>N</INF>Ar reaction for a first-in-class RIP1 kinase inhibitor GSK2982772 in clinical trials
Tetrahedron Lett 2017, 58(23): 2306
Harris, P.A.
Identification of a first-in-class RIP1 kinase inhibitor in phase 2a clinical trials for immunoinflammatory diseases
ACS MEDI-EFMC Med Chem Front (June 25-28, Philadelphia) 2017, Abst 

Harris, P.
Identification of a first-in-class RIP1 kinase inhibitor in phase 2a clinical trials for immuno-inflammatory diseases
253rd Am Chem Soc (ACS) Natl Meet (April 2-6, San Francisco) 2017, Abst MEDI 313

1H NMR AND 13C NMR PREDICT

////////////GSK 2982772, phase 2, Plaque psoriasis, Rheumatoid arthritis, Ulcerative colitis

CN3c4ccccc4OC[C@H](NC(=O)c2nnc(Cc1ccccc1)n2)C3=O

Eravacycline

http://www.ama-assn.org/resources/doc/usan/eravacycline.pdf

1-Pyrrolidineacetamide, N-[(5aR,6aS,7S,10aS)-9-(aminocarbonyl)-7-(dimethylamino)-
4-fluoro-5,5a,6,6a,7,10,10a,12-octahydro-1,8,10a,11-tetrahydroxy-10,12-dioxo-2-
naphthacenyl]-
(4S,4aS,5aR,12aS)-4-(dimethylamino)-7-fluoro-3,10,12,12a-tetrahydroxy-1,11-dioxo-9-
[(pyrrolidin-1-ylacetyl)amino]-1,4,4a,5,5a,6,11,12a-octahydrotetracene-2-carboxamide

MOLECULAR FORMULA C27H31FN4O8
MOLECULAR WEIGHT 558.6

SPONSOR Tetraphase Pharmaceuticals, Inc.
CODE DESIGNATION TP-434
CAS REGISTRY NUMBER 1207283-85-9
WHO NUMBER 9702

Eravacycline (TP-434) is a synthetic fluorocycline antibiotic in development by Tetraphase Pharmaceuticals. It is closely related to the glycylglycine antibiotic tigecycline and the tetracycline class of antibiotics. It has a broad spectrum of activity including many multi-drug resistant strains of bacteria. Phase III studies in complicated intra-abdominal infections (cIAI) ^[1] and complicated urinary tract infections (cUTI)^[2] were recently completed with mixed results. Eravacylcine has been designated as a Qualified Infectious Disease Product (QIDP), as well as for fast track approval by the FDA.^[3]

WO2010017470A1

Example 1. Synthesis of Compounds of Structural Formula (I).

The compounds of the invention can be prepared according the synthetic scheme shown in Scheme 1.

Compound 34

¹H NMR (400 MHz, CD₃OD) δ 8 22 (d, J= 1 1.0 Hz, 1 H), 4.33 (s, 2H), 4.10 (S₃ 1H), 3 83-3.72 (m, 2H), 3.25-2.89 (m, 12H), 2.32-2.00 (m, 6H), 1.69-1.56 (m, 1H); MS (ESI) m/z 559.39 (M+H).

Medical Uses

Eravacycline has shown broad spectrum of activity against a variety of Gram-positive and Gram-negative bacteria, including multi-drug resistant strains, such as methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Enterobacteriaceae.^[4] It is currently being formulated as for intravenous and oral administration.

PATENT

WO 2016065290

Eravacylme is a tetracycline antibiotic that has demonstrated broad spectrum activity against a wide variety of multi-drug resistant Gram-negative, Gram-positive and anaerobic bacteria in humans. In Phase I and Phase II clinical trials, eravacycline also demonstrated a favorable safety and tolerability profile. In view of its attractive

pharmacological profile, synthetic routes to eravacycline and, in particular, synthetic routes that result in suitable quantities of eravacycline for drag development and manufacturing, are becoming increasingly important.

As described in International Publication No . WO 2010/017470, eravacycline is conveniently synthesized from 7-fluorosancycline, another tetracycline. 7-Fluorosancycline can be synthesized, in turn, from commercially available 7-ammosancycline or a protected derivative thereof. However, very few procedures for the conversion of (^-ammo-substituted tetracyclines, such as 7-aminosancycline, to C7-fiuoro-substituted tetracyclines, such as 7-fluorosancycline, have been reported, and those that have are not suitable to be deployed at production-scale.

Therefore, there is a need for improved processes, particularly improved production -scale processes, for converting C7-amino-substituted tetracyclines to C7-fluoro-substituted tetracyclines.

Example 3. Preparation of Eravacycline From 9-Aminosancycline Using a Photolytic Fluorination

[00158] Sancycline (0.414 g, 1.0 mmol) was dissolved in trifiuoroacetic acid (TFA). The solution was cooled to 0 °C. To the solution was added N-bromosuccinimide (NBS, 0.356 g, 2.1 mmol). The reaction was complete after stirring at 0 °C for 1 h. The reaction mixture was allowed to warm to rt. Solid NO3 (0.1 Ig, 0.11 mrnoi) was added and the reaction mixture was stirred at rt for 1 h. The reaction solution was added to 75 mL cold diethyl ether. The precipitate was collected by filtration and dried to give 0.46 g of compound 6. Compound 6 can then be reduced to compounds 7, 8, or 9 using standard procedures.

13

[00159] 9-Aminosancycline (7, 1 g, 0233 mmol) was dissolved in 20 mL sulfuric acid and the reaction was cooled using an ice bath. Potassium nitrate (235 mg, 0.233 mmol) was added in several portions. After stirring for 15 min, the reaction mixture was added to 400 mL MTBE followed by cooling using an ice bath. The solid was collected by filtration. The filter cake was dissolved in 10 mL water and the pH of the aqueous solution was adjusted to 5.3 using 25% aqueous NaOH. The resulting suspension was filtered, and the filter cake was dried to give 1 g compound 10: MS (ESI) m/z 475.1 (M+l).

[00160] Compound 10 (1.1 g) was dissolved in 20 mL of water and 10 mL of acetonitrile. To the solution was added acyl chloride 3 (in two portions: 600 mg and 650 mg). The pH of the reaction mixture was adjusted to 3.5 using 25% aqueous NaOH. Another portion of acyl chloride (800 mg) was added. The reaction was monitored by HPLC analysis. Product 11 was isolated from the reaction mixture by preparative HPLC. Lyophilization gave 1.1 g of compound 11: MS (ESI) m/z 586.3 (M+l).

[00161] Compound 11 (1.1 g) was dissolved in methanol. To the solution was added concentrated HC1 (0.5 mL) and 10% Pd-C (600 mg). The reaction mixture was stirred under a hydrogen atmosphere (balloon). After the reaction was completed, the catalyst was removed by filtration. The filtrate was concentrated to give 1 g of compound 12: ‘H NMR (400 MHz, DMSO), 8.37 (s, 1H), 4.38-4.33 (m, 3H), 3.70 (br s, 2H), 3.30-2.60 (m, 1211), 2.36-2.12 (m, 2H), 2.05-1.80 (m, 4H), 1.50-1.35 (m, 1H); MS (ESI) m/z 556.3 (M+l).

[00162] Compound 12 (150 mg) was dissolved in 1 mL of 48% HBF₄. To the solution was added 21 mg of NaN0₂. After compound 12 was completely converted to compound 13 (LC/MS m/z 539.2), the reaction mixture was irradiated with 254 nm light for 6 h while being cooled with running water. The reaction mixture was purified by preparative HPLC using acetonitrile and 0.05 N aqueous HCl as mobile phases to yield the compound 4 (eravacyclme, 33 mg) as a bis-HCl salt (containing 78% of 4 and 10% of the 7-H byproduct, by HPLC): MS (ESI) m/z 559.3 (M+l).

PAPER

Exploring the Boundaries of “Practical”: De Novo Syntheses of Complex Natural Product-Based Drug Candidates

PAPER

Journal of Medicinal Chemistry (2012), 55(2), 597-605

Fluorocyclines. 1. 7-Fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline: A Potent, Broad Spectrum Antibacterial Agent

This and the accompanying report (DOI: 10.1021/jm201467r) describe the design, synthesis, and evaluation of a new generation of tetracycline antibacterial agents, 7-fluoro-9-substituted-6-demethyl-6-deoxytetracyclines (“fluorocyclines”), accessible through a recently developed total synthesis approach. These fluorocyclines possess potent antibacterial activities against multidrug resistant (MDR) Gram-positive and Gram-negative pathogens. One of the fluorocyclines, 7-fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline (17j, also known as TP–434, 50th Interscience Conference on Antimicrobial Agents and Chemotherapy Conference, Boston, MA, September 12–15, 2010, poster F1–2157), is currently undergoing phase 2 clinical trials in patients with complicated intra-abdominal infections (cIAI).

(4S,4aS,5aR,12aS)-4-(Dimethylamino)-7-fluoro-3,10,12,12a-tetrahydroxy-1,11-dioxo-9-[2-(pyrrolidin-1-yl)acetamido]-1,4,4a,5,5a,6,11,12a-octahydrotetracene-2-carboxamide (17j)

PAPER

Journal of Organic Chemistry (2017), 82(2), 936-943

A Divergent Route to Eravacycline

Wu-Yan Zhang^* , Qinglin Che, Scott Crawford, Magnus Ronn, and Nicholas Dunwoody

Tetraphase Pharmaceuticals, Inc., 480 Arsenal Way, Suite 110, Watertown, Massachusetts 02472, United States

J. Org. Chem., 2017, 82 (2), pp 936–943

DOI: 10.1021/acs.joc.6b02442

*E-mail: wzhang@tphase.com.

Abstract

A convergent route to eravacycline (1) has been developed by employing Michael–Dieckmann cyclization between enone 3 and a fully built and protected left-hand piece (LHP, 2). After construction of the core eravacycline structure, a deprotection reaction was developed, allowing for the isoxazole ring opening and global deprotection to be achieved in one pot. The LHP is synthesized from readily available 4-fluoro-3-methylphenol in six steps featuring a palladium-catalyzed phenyl carboxylation in the last step.

Eravacycline di-HCl salt (1) as a yellow solid: purity 97.9%; mp 197–199 °C dec. The spectral data matched those from original sample as reported in our previous publication.(3)

3 Ronn, M.; Zhu, Z.; Hogan, P. C.; Zhang, W.-Y.; Niu, J.; Katz, C. E.; Dunwoody, N.; Gilicky, O.; Deng, Y.;Hunt, D. K.; He, M.; Chen, C.-L.; Sun, C.; Clark, R. B.; Xiao, X.-Y. Org. Process Res. Dev. 2013, 17, 838–845, DOI: 10.1021/op4000219

PAPER

WO 2016065290

PAPER

Organic Process Research & Development (2013), 17(5), 838-845

 

Process research and development of the first fully synthetic broad spectrum 7-fluorotetracycline in clinical development is described. The process utilizes two key intermediates in a convergent approach. The key transformation is a Michael–Dieckmann reaction between a suitable substituted aromatic moiety and a key cyclohexenone derivative. Subsequent deprotection and acylation provide the desired active pharmaceutical ingredient in good overall yield.

Free base of 7. HPLC (248 nm) showed 97.1% purity with 0.80% of the corresponding impurity from 19, 1.2% of epimer of 7, and 0.80% the corresponding impurity from 20 (102g, 88.7% yield) product as a yellow solid.

¹H NMR (CDCl₃, 400 MHz, δ): 9.81 (d, 1H), 3.29 (s, 2H), 3.04 (m, 3H); 2.68 (bs, 4H), 2.62 (m, 1H), 2.44 (bs, 6H), 2.23 (t, 1H), 1.99 (s, 1H), 1.84 (bs, 4H), 1.5 (bs, 1H).

MS (ES) m/z calcd for +H: 559.2 (100.0), 560.2 (29.9), 561.2 (5.9); found: 559.3, 560.2, 561.3.

Give 7·2HCl (531 g containing 6.9% by weight water, ∼ 784 mmol). HPLC (248 nm) indicated a 96.6% purity with 0.64% of the corresponding impurity from 19, 1.3% of epimer of 7, and 1.3% the corresponding impurity from 20.

¹H NMR, (d₆-DMSO, 400 MHz, δ): 11.85 (s, 1H), 10.28 (s, 1H), 9.56 (s, 1H); 8.99 (s, 1H), 8.04 (d, J = 10.95 Hz, 1H), 4.32 (m, 1H), 4.30 (s, 1H), 3.58 (bs, 2H), 3.09 (bs, 2H), 3.007 (m, 1H); 2.94 (m, 2H), 2.8 (s, 6H), 2.15–2.32 (m, 2H), 1.92 (bd, 4H), 1.44 (m, 1H).

¹³C NMR (d₆-DMSO, 100 MHz)193.74, 191.84, 187.45, 175.72, 171.88, 164.45, 152.12, 151.26, 148.93, 148.86, 125.13, 125.03, 122.79, 122.60, 116.00, 115.72, 115.25, 108.12, 95.38, 74.06, 67.78, 55.47, 53.91, 34.95, 33.98, 31.41, 26.45, 22.9.

MS (ES) m/zcalcd for +H: 559.2 (100.0), 560.2 (29.9), 561.2 (5.9); found: 559.3, 560.2, 561.3.

PAPER

Natural product synthesis in the age of scalability – Natural …

10.1039/C3NP70090A

Tetracycline (Myers/Tetraphase, 2005–2013). Myers’ convergent approach to the tetracyclines is a great example of how a scalable synthesis of a key intermediate en route to a natural product can fuel the discovery of entirely new drug candidates. These broad-spectrum polyketide antibiotics have been widely used in human and veterinary medicine, but, due to the development of tetracycline-resistant strains, there is an unmet need for novel tetracycline drugs. Pioneering work in this eld has been achieved by the Myers’ group, who published a landmark synthetic approach to the tetracycline class of antibiotics in 2005.16 Using this route, over 3,000 fully synthetic tetracyclines have been prepared to date. Central to their strategy was the synthesis of a highly versatile intermediate, AB enone 7, 17 which enabled the convergent construction of novel tetracycline antibiotics (Scheme 3, A).18 Naturally, the route to 7 had to be practical and amenable to large-scale synthesis and consequently, the synthetic approaches to this building block have become more and more practical and efficient with every new generation. In 2007, Myers published their rst practical and enantioselective approach to 7 (Scheme 3, B).17 The route started from 8, which can be accessed in multi-hundred gram amounts from commercially available 3-hydroxy-5-isoxazolecarboxylate (not shown) by O-benzylation followed by DIBAL reduction. In a three-step sequence, 8 was transformed into carbinol 9. In the key step of the sequence, 9 underwent an intramolecular Diels–Alder reaction to give a mixture of 4 diastereomeric cycloadducts, which, aer Swern oxidation, could be readily separated by ash column chromatography to afford 10. Finally, boron trichloride mediated opening of the oxabicyclic ring system and demethylation, followed by TBS protection of the tertiary hydroxyl-group, afforded 40 g of the AB enone 7 in 21% overall yield, over nine steps from commercial material. Slight modications of this route have allowed for the preparation of >20 kg batches of the AB enone. The availability of large-scale batches of 7 has both enabled the discovery and the development of eravacycline (11), the rst fully synthetic tetracycline analog in clinical development, from Tetraphase Pharmaceuticals. In their process route,19 the key Michael– Dieckmann cyclization between 7 and 12 was carried out on kg-scale and afforded 13 in 93.5% yield. This compound was transformed into eravacycline (11) in 3 more steps, including TBS-cleavage, hydrogenolysis and amide bond formation. Using this process, several kg of 11 have been prepared to date to support clinical studies. Finally, a third- and fourth-generation route to 7 has recently been published by Myers that is not only shorter than previous routes, but also amenable of structural modications of the AB-ring enone.20

16 M. G. Charest, C. D. Lerner, J. D. Brubaker, D. R. Siegel and A. G. Myers, Science, 2005, 308, 395–398. 17 J. D. Brubaker and A. G. Myers, Org. Lett., 2007, 9, 3523–3525. 18 (a) C. Sun, Q. Wang, J. D. Brubaker, P. M. Wright, C. D. Lerner, K. Noson, M. Charest, D. R. Siegel, Y.-M. Wang and A. G. Myers, J. Am. Chem. Soc., 2008, 130, 17913–17927; (b) X.-Y. Xiao, D. K. Hunt, J. Zhou, R. B. Clark, N. Dunwoody, C. Fyfe, T. H. Grossman, W. J. O’Brien, L. Plamondon, M. R¨onn, C. Sun, W.-Y. Zhang and J. A. Sutcliffe, J. Med. Chem., 2012, 55, 597–605; (c) R. B. Clark, M. He, C. Fyfe, D. Loand, W. J. O’Brien, L. Plamondon, J. A. Sutcliffe and X.-Y. Xiao, J. Med. Chem., 2011, 54, 1511–1528; (d) R. B. Clark, D. K. Hunt, M. He, C. Achorn, C.-L. Chen, Y. Deng, C. Fyfe, T. H. Grossman, P. C. Hogan, W. J. O’Brien, L. Plamondon, M. R¨onn, J. A. Sutcliffe, Z. Zhu and X.-Y. Xiao, J. Med. Chem., 2012, 55, 606–622; (e) C. Sun, D. K. Hunt, R. B. Clark, D. Loand, W. J. O’Brien, L. Plamondon and X.-Y. Xiao, J. Med. Chem., 2011, 54, 3704–3731. 19 M. Ronn, Z. Zhu, P. C. Hogan, W.-Y. Zhang, J. Niu, C. E. Katz, N. Dunwoody, O. Gilicky, Y. Deng, D. K. Hunt, M. He, C.-L. Chen, C. Sun, R. B. Clark and X.-Y. Xiao, Org. Process Res. Dev., 2013, 17, 838–845. 20 D. A. Kummer, D. Li, A. Dion and A. G. Myers, Chem. Sci., 2011, 2, 1710–1718. 21 (a) G. R. Pettit, Z. A. Chicacz, F. Gao, C. L. Herald, M. R. Boyd, J. M. Schmidt and J. N. A. Hooper, J. Org. Chem., 1993, 58, 1302–1304; (b) M. Kobayashi, S. Aoki, H. Sakai, K. Kawazoe, N. Kihara, T. Sasaki and I. Kitagawa, Tetrahedron Lett., 1993, 34, 2795–2798. 22 (a) J. Guo, K. J. Duffy, K. L. Stevens, P. I. Dalko, R. M. Roth, M. M. Hayward and Y. Kishi, Angew. Chem., Int. Ed., 1998, 37, 187–190; (b) M. M. Hayward, R. M. Roth, K. J. Duffy, P. I. Dalko, K. L. Stevens, J. Guo and Y. Kishi, Angew. Chem., Int. Ed., 1998, 37, 190–196; (c) I. Paterson, D. Y. K. Chen, M. J. Coster, J. L. Acena, J. Bach, ˜ K. R. Gibson, L. E. Keown, R. M. Oballa, T. Trieselmann, D. J. Wallace, A. P. Hodgson and R. D. Norcross, Angew. Chem., Int. Ed., 2001, 40, 4055–4060; (d) M. T. Crimmins, J. D. Katz, D. G. Washburn, S. P. Allwein and L. F. McAtee, J. Am. Chem. Soc., 2002, 124, 5661–5663; (e) M. Ball, M. J. Gaunt, D. F. Hook, A. S. Jessiman, S. Kawahara, P. Orsini, A. Scolaro, A. C. Talbot, H. R. Tanner, S. Yamanoi and S. V. Ley, Angew. Chem., Int. Ed., 2005, 44, 5433–5438. 23 A. B. Smith, T. Tomioka, C. A. Risatti, J. B. Sperry and C. Sfouggatakis, Org. Lett., 2008, 10, 4359–4362. 24 (a) U. Eder, G. Sauer and R. Wiechert, Angew. Chem., Int. Ed. Engl., 1971, 10, 496–497; (b) Z. G. Hajos and D. R. Parrish, J. Org. Chem., 1974, 39, 1615–1621; (c) B. List, Tetrahedron, 2002, 58, 5573–5590; (d) A. B. Northrup and D. W. C. MacMillan, Science, 2004, 305, 1752–1755; (e) A. B. Northrup, I. K. Mangion, F. Hettche and D. W. C. MacMillan, Angew. Chem., Int. Ed., 2004, 43, 2152– 2154. 25 A. B. Smith, C. Sfouggatakis, D. B. Gotchev, S. Shirakami, D. Bauer, W. Zhu and V. A. Doughty, Org. Lett., 2004, 6, 3637–3640. 26 A. B. Smith, C. A. Risatti, O. Atasoylu, C. S. Bennett, J. Liu, H. Cheng, K. TenDyke and Q. Xu, J. Am. Chem. Soc., 2011, 133, 14042–14053. 27 A. R. Carroll, E. Hyde, J. Smith, R. J. Quinn, G. Guymer and P. I. Forster, J. Org. Chem., 2005, 70, 1096–1099. 2W. J. O’Brien, L. Plamondon, M. R¨onn, C. Sun, W.-Y. Zhang and J. A. Sutcliffe, J. Med. Chem., 2012, 55, 597–605; (c) R. B. Clark, M. He, C. Fyfe, D. Loand, W. J. O’Brien, L. Plamondon, J. A. Sutcliffe and X.-Y. Xiao, J. Med. Chem., 2011, 54, 1511–1528; (d) R. B. Clark, D. K. Hunt, M. He, C. Achorn, C.-L. Chen, Y. Deng, C. Fyfe, T. H. Grossman, P. C. Hogan, W. J. O’Brien, L. Plamondon, M. R¨onn, J. A. Sutcliffe, Z. Zhu and X.-Y. Xiao, J. Med. Chem., 2012, 55, 606–622; (e) C. Sun, D. K. Hunt, R. B. Clark, D. Loand, W. J. O’Brien, L. Plamondon and X.-Y. Xiao, J. Med. Chem., 2011, 54, 3704–3731. 19 M. Ronn, Z. Zhu, P. C. Hogan, W.-Y. Zhang, J. Niu, C. E. Katz, N. Dunwoody, O. Gilicky, Y. Deng, D. K. Hunt, M. He, C.-L. Chen, C. Sun, R. B. Clark and X.-Y. Xiao, Org. Process Res. Dev., 2013, 17, 838–845. 20 D. A. Kummer, D. Li,

PAPER

10.1039/C3CC49694E

In 2005, Myers and co-workers reported the first use of 4 in complex natural product total synthesis.13 From their previously reported building block 43, tricyclic diketone 59 was accessible in a further 7 steps (10% overall yield from benzoate,   Scheme 7). Diketone 59 serves as a common precursor to the tetracycline AB-ring system and may be coupled with D-ring precursors such as 60 by a Michael–Dieckmann cascade cyclisation that forms the C-ring. Thus, after deprotection, the natural product ()-6-deoxytetracycline 61 is accessible in 14 steps and 7.0% overall yield from benzoate. Several points about the synthesis are noteworthy. The yield represents an improvement of orders of magnitude over the yields for all previously reported total syntheses of tetracyclines. Thus, for the first time, novel tetracycline analogues became accessible in useful quantities; union of 62 with 59 to access 63 is a representative example. Secondly, previous total syntheses of tetracyclines had been bedevilled by the difficulty of installing the C12a tertiary alcohol at a late stage.14c The Myers approach is conceptually distinct in that the C12a hydroxyl group is installed in the very first step, i.e. it is the hydroxyl group deriving from the microbial ipso hydroxylation. Finally, apart from the C12a stereocentre, all other stereocentres in the final tetracyclines are set under substrate control. Thus, all the stereochemical information in the final products may be considered ultimately to be of enzymatic origin. In the years following the Myers group’s initial disclosure, the methodology has been extended and improved to allow for the preparation of a greater diversity of novel tetracycline analogues.14 This has culminated in the development of eravacycline 65 (accessed from 59 and 64) by Tetraphase Pharmaceuticals.15 Eravacycline is indicated for treatment of multidrug-resistant infections and is currently in phase III trials.

13 (a) M. G. Charest, C. D. Lerner, J. D. Brubaker, D. R. Siegel and A. G. Myers, Science, 2005, 308, 395; (b) M. G. Charest, D. R. Siegel and A. G. Myers, J. Am. Chem. Soc., 2005, 127, 8292.

14 (a) J. D. Brubaker and A. G. Myers, Org. Lett., 2007, 9, 3523; (b) C. Sun, Q. Wang, J. D. Brubaker, P. M. Wright, C. D. Lerner, K. Noson, M. Charest, D. R. Siegel, Y.-M. Wang and A. G. Myers, J. Am. Chem. Soc., 2008, 130, 17913; (c) D. A. Kummer, D. Li, A. Dion and A. G. Myers, Chem. Sci., 2011, 2, 1710; (d) P. M. Wright and A. G. Myers, Tetrahedron, 2011, 67, 9853.

15 (a) R. B. Clark, M. He, C. Fyfe, D. Lofland, W. J. O’Brien, L. Plamondon, J. A. Sutcliffe and X.-Y. Xiao, J. Med. Chem., 2011, 54, 1511; (b) C. Sun, D. K. Hunt, R. B. Clark, D. Lofland, W. J. O’Brien, L. Plamondon and X.-Y. Xiao, J. Med. Chem., 2011, 54, 3704; (c) X.-Y. Xiao, D. K. Hunt, J. Zhou, R. B. Clark, N. Dunwoody, C. Fyfe, T. H. Grossman, W. J. O’Brien, L. Plamondon, M. Ro¨nn, C. Sun, W.-Y. Zhang and J. A. Sutcliffe, J. Med. Chem., 2012, 55, 597; (d) R. B. Clark, D. K. Hunt, M. He, C. Achorn, C.-L. Chen, Y. Deng, C. Fyfe, T. H. Grossman, P. C. Hogan, W. J. O’Brien, L. Plamondon, M. Ro¨nn, J. A. Sutcliffe, Z. Zhu and X.-Y. Xiao, J. Med. Chem., 2012, 55, 606; (e) M. Ronn, Z. Zhu, P. C. Hogan, W.-Y. Zhang, J. Niu, C. E. Katz, N. Dunwoody, O. Gilicky, Y. Deng, D. K. Hunt, M. He, C.-L. Chen, C. Sun, R. B. Clark and X.-Y. Xiao, Org. Process Res. Dev., 2013, 17, 838; ( f ) R. B. Clark, M. He, Y. Deng, C. Sun, C.-L. Chen, D. K. Hunt, W. J. O’Brien, C. Fyfe, T. H. Grossman, J. A. Sutcliffe, C. Achorn, P. C. Hogan, C. E. Katz, J. Niu, W.-Y. Zhang, Z. Zhu, M. Ro¨nn and X.-Y. Xiao, J. Med. Chem., 2013, 56, 8112.

WO 2017125557, Crystalline forms of eravacycline dihydrochloride or its solvates or hydrates. Also claims a process for the preparation of an eravacycline intended for oral or parenteral use, for the treatment of bacterial infections, preferably intra-abdominal and urinary tract infections caused by multidrug resistant gram negative pathogens. Follows on from WO2017097891 .

Tetraphase Pharmaceuticals is developing eravacycline, a fully synthetic fluorocycline antibiotic and the lead from a series of tetracycline analogs which includes TP-221 and TP-170, for treating bacterial infections.

Eravacycline is a tetracycline antibiotic chemically designated (4S,4aS,5aR,l2aS)-4-(Dimethylamino)-7-fluoro-3 ,10,12,12a-tetrahydroxy- 1,11 -dioxo-9-[2-(-pyrrolidin- 1 -yl)acetamido]-l,4,4a,5,5a,6,l l ,12a-octahydrotetracene-2-carboxamide and can be represented by the following chemical structure according to formula (I).

formula (I)

Eravacycline possesses antibacterial activity against Gram negative pathogens and Gram positive pathogens, in particular against multidrug resistant (MDR) Gram negative pathogens and is currently undergoing phase III clinical trials in patients suffering from complicated intraabdominal infections (cIAI) and urinary tract infections (cUTI).

WO 2010/017470 Al discloses eravacycline as compound 34. Eravacycline is described to be prepared according to a process, which is described in more detail only for related compounds.

The last step of this process involves column chromatography with diluted hydrochloric acid/ acetonitrile, followed by freeze drying.

WO 2012/021829 Al discloses pharmaceutically acceptable acid and base addition salts of eravacycline in general and a general process for preparing the same involving reacting eravacycline free base with the corresponding acids and bases, respectively. On page 15, lines 3 to 6, a lyophilized powder containing an eravacycline salt and mannitol is disclosed.

Xiao et. al. “Fluorocyclines. 1. 7-Fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline: A Potent, Broad Spectrum Antibacterial Agent” J. Med. Chem. 2012, 55, 597-605 synthesized eravacycline following the procedure for compounds 17e and 17i on page 603. After preparative reverse phase HPLC, compounds 17e and 17i were both obtained as bis-hydrochloride salts in form of yellow solids.

Ronn et al. “Process R&D of Eravacycline: The First Fully Synthetic Fluorocycline in Clinical Development” Org. Process Res. Dev. 2013, 17, 838-845 describe a process yielding eravacycline bis-hydrochloride as the final product. The last step involves precipitation of eravacycline bis-hydrochloride salt by adding ethyl acetate as an antisolvent to a solution of eravacycline bis-hydrochloride in an ethanol/ methanol mixture. The authors describe in some detail the difficulties during preparation of the bis-hydrochloride salt of eravacycline. According to Ronn et al. “partial addition of ethyl acetate led to a mixture containing suspended salt and a gummy form of the salt at the bottom of the reactor. At this stage, additional ethanol was added, and the mixture was aged with vigorous stirring until the gummy material also became a suspended solid.” In addition, after drying under vacuum the solid contained “higher than acceptable levels of ethanol”. “The ethanol was then displaced by water by placing a tray containing the solids obtained in a vacuum oven at reduced pressure (…) in the presence of an open vessel of water.” At the end eravacycline bis-hydrochloride salt containing about 4 to 6% residual moisture was obtained. The authors conclude that there is a need for additional improvements to the procedure along with an isolation step suitable for large scale manufacturing.

It is noteworthy that eravacycline or its salts are nowhere described as being a crystalline solid and that the preparation methods used for the preparation of eravacycline are processes like lyophilization, preparative column chromatography and precipitation, which typically yield amorphous material.

The cumbersome process of Ronn et al. points towards problems in obtaining eravacycline bis-hydrochloride in a suitable solid state, problems with scaleability of the available production process as well as problems with the isolation and drying steps of eravacycline.

In addition, amorphous solids can show low chemical stability, low physical stability, hygroscopicity, poor isolation and powder properties, etc.. Such properties are drawbacks for the use as an active pharmaceutical ingredients.

Thus, there is a need in pharmaceutical development for solid forms of an active pharmaceutical ingredient which demonstrate a favorable profile of relevant properties for formulation as a pharmaceutical composition, such as high chemical and physical stability, improved properties upon moisture contact, low(er) hygroscopicity and improved powder properties.

WO2010017470

WO 2017125557

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2017125557&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription

The invention relates to crystalline eravacycline bis-hydrochloride and to a process for its preparation. Furthermore, the invention relates to the use of crystalline eravacycline bis-hydrochloride for the preparation of pharmaceutical compositions. The invention further relates to pharmaceutical compositions comprising an effective amount of crystalline eravacycline bis-hydrochloride. The pharmaceutical compositions of the present invention can be used as medicaments, in particular for treatment and/ or prevention of bacterial infections e.g. caused by Gram negative pathogens or Gram positive pathogens, in particular caused by multidrug resistant Gram negative pathogens. The pharmaceutical compositions of the present invention can thus be used as medicaments for e.g. the treatment of complicated intra-abdominal and urinary tract infection

References

1. ^ Jump up to:^a b Solomkin, Joseph; Evans, David; Slepavicius, Algirdas; Lee, Patrick; Marsh, Andrew; Tsai, Larry; Sutcliffe, Joyce A.; Horn, Patrick (2016-11-16). “Assessing the Efficacy and Safety of Eravacycline vs Ertapenem in Complicated Intra-abdominal Infections in the Investigating Gram-Negative Infections Treated With Eravacycline (IGNITE 1) Trial: A Randomized Clinical Trial”. JAMA surgery. ISSN 2168-6262. PMID 27851857. doi:10.1001/jamasurg.2016.4237.
2. ^ Jump up to:^a b “Tetraphase Announces Top-Line Results From IGNITE2 Phase 3 Clinical Trial of Eravacycline in cUTI (NASDAQ:TTPH)”. ir.tphase.com. Retrieved 2016-11-20.
3. Jump up^ “FDA Grants QIDP Designation to Eravacycline, Tetraphase’s Lead Antibiotic Product Candidate | Business Wire”. http://www.businesswire.com. Retrieved 2016-11-20.
4. ^ Jump up to:^a b Zhanel, George G.; Cheung, Doris; Adam, Heather; Zelenitsky, Sheryl; Golden, Alyssa; Schweizer, Frank; Gorityala, Bala; Lagacé-Wiens, Philippe R. S.; Walkty, Andrew (2016-04-01). “Review of Eravacycline, a Novel Fluorocycline Antibacterial Agent”. Drugs. 76 (5): 567–588. ISSN 1179-1950. PMID 26863149. doi:10.1007/s40265-016-0545-8.
5. Jump up^ Sutcliffe, J. A.; O’Brien, W.; Fyfe, C.; Grossman, T. H. (2013-11-01). “Antibacterial activity of eravacycline (TP-434), a novel fluorocycline, against hospital and community pathogens”. Antimicrobial Agents and Chemotherapy. 57 (11): 5548–5558. ISSN 1098-6596. PMC 3811277 . PMID 23979750. doi:10.1128/AAC.01288-13.
6. Jump up^ Solomkin, Joseph S.; Ramesh, Mayakonda Krishnamurthy; Cesnauskas, Gintaras; Novikovs, Nikolajs; Stefanova, Penka; Sutcliffe, Joyce A.; Walpole, Susannah M.; Horn, Patrick T. (2014-01-01). “Phase 2, randomized, double-blind study of the efficacy and safety of two dose regimens of eravacycline versus ertapenem for adult community-acquired complicated intra-abdominal infections”. Antimicrobial Agents and Chemotherapy. 58 (4): 1847–1854. ISSN 1098-6596. PMC 4023720 . PMID 24342651. doi:10.1128/AAC.01614-13.
7. Jump up^ Abdallah, Marie; Olafisoye, Olawole; Cortes, Christopher; Urban, Carl; Landman, David; Quale, John (2015-03-01). “Activity of eravacycline against Enterobacteriaceae and Acinetobacter baumannii, including multidrug-resistant isolates, from New York City”. Antimicrobial Agents and Chemotherapy. 59 (3): 1802–1805. ISSN 1098-6596. PMC 4325809 . PMID 25534744. doi:10.1128/AAC.04809-14.
8. Jump up^ Fyfe, Corey; LeBlanc, Gabrielle; Close, Brianna; Nordmann, Patrice; Dumas, Jacques; Grossman, Trudy H. (2016-08-22). “Eravacycline is active against bacterial isolates expressing the polymyxin resistance gene mcr-1”. Antimicrobial Agents and Chemotherapy. 60: 6989–6990. ISSN 0066-4804. PMC 5075126 . PMID 27550359. doi:10.1128/AAC.01646-16.
9. Jump up^ “http://www.healio.com/infectious-disease/antimicrobials/news/online/%7B3b5e5b8a-a5eb-4739-a402-3c88c22621d4%7D/phase-3-ignite4-trial-to-examine-safety-efficacy-of-iv-eravacycline-in-ciais”. http://www.healio.com. Retrieved 2016-11-20. External link in |title= (help)
10. ^ Jump up to:^a b “Tetraphase Pharmaceuticals Provides Update on Eravacycline Regulatory and Development Status (NASDAQ:TTPH)”. ir.tphase.com. Retrieved 2016-11-20.
11. ^ Jump up to:^a b c “Tetraphase Announces Positive Top-Line Results from Phase 3 IGNITE4 Clinical Trial in Complicated Intra-Abdominal Infections (NASDAQ:TTPH)”. ir.tphase.com. Retrieved 2017-07-27.
12. ^ Jump up to:^a b “Efficacy and Safety Study of Eravacycline Compared With Meropenem in Complicated Intra-abdominal Infections – Full Text View – ClinicalTrials.gov”. http://www.clinicaltrials.gov. Retrieved 2017-07-27.
13. Jump up^ “http://www.healio.com/infectious-disease/antimicrobials/news/online/%7B8b0a64f5-6a4c-4b88-b5ac-9c1fe100778c%7D/ignite2-eravacycline-inferior-to-levofloxacin-but-iv-formulation-shows-promise”. http://www.healio.com. Retrieved 2016-11-20. External link in |title= (help)
14. ^ Jump up to:^a b “Efficacy and Safety Study of Eravacycline Compared With Ertapenem in Participants With Complicated Urinary Tract Infections – Full Text View – ClinicalTrials.gov”. http://www.clinicaltrials.gov. Retrieved 2017-07-27.
15. ^ Jump up to:^a b “Tetraphase Pharmaceuticals Doses First Patient in IGNITE3 Phase 3 Clinical Trial of Once-daily IV Eravacycline in cUTI (NASDAQ:TTPH)”. ir.tphase.com. Retrieved 2017-07-27.
16. Jump up^ “Tetraphase reports 3Q loss”. Retrieved 2016-11-20.
17. Jump up^ Feroldi, Brian (2016-11-20). “Why Tetraphase Pharmaceuticals Dropped 74% of Its Value in 2015 — The Motley Fool”. The Motley Fool. Retrieved 2016-11-20.

External links

• “Tetraphase Announces Top-Line Results From IGNITE2 Phase 3 Clinical Trial of Eravacycline in cUTI: Eravacycline Did Not Achieve Primary Endpoint in Pivotal Portion of cUTI Trial”
• Tetraphase pipeline
  

Notes

• Process R&D of Eravacycline: The First Fully Synthetic Fluorocycline in Clinical Development

Eravacycline

Names
IUPAC name (4S,4aS,5aR,12aS)-4-(Dimethylamino)-7-fluoro-3,10,12,12a-tetrahydroxy-1,11-dioxo-9-[(1-pyrrolidinylacetyl)amino]-1,4,4a,5,5a,6,11,12a-octahydro-2-tetracenecarboxamide
Identifiers
CAS Number	1207283-85-9
3D model (JSmol)	Interactive image
ChemSpider	28495485
KEGG	D10421
PubChem CID	54726192
InChI[show]
SMILES[show]
Properties
Chemical formula	C27H31FN4O8
Molar mass	558.555

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OLD DATA FROM PREVIOUS BLOG POST

Tetraphase Pharmaceuticals Inc. (NASDAQ:TTPH) today announced that it will present two posters at IDWeek 2013 that examine the potential of its lead antibiotic candidate eravacycline to treat serious multi-drug resistant (MDR) infections. The first will highlight positive results of a Phase 1 study assessing the bronchopulmonary disposition safety and tolerability of eravacycline in healthy men and women; this study represents the first clinical assessment of eravacycline for potential use in treating pneumonia. The second poster will provide the results of a study that examined the activity of eravacycline in vitro against multiple Gram-negative and Gram-positive pathogens to set quality-control limits for monitoring eravacycline activity in future testing programs.
http://www.pharmiweb.com/pressreleases/pressrel.asp?ROW_ID=79335#.Uk6MOoanonU
More: http://www.pharmiweb.com/pressreleases/pressrel.asp?ROW_ID=79335#.Uk6MOoanonU#ixzz2gkEMTtQm

Eravacycline (TP-434) is a synthetic fluorocycline antibiotic in development.

Eravacycline (TP-434 or 7-fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline) is a novel fluorocycline that was evaluated for antimicrobial activity against panels of recent aerobic and anaerobic Gram-negative and Gram-positive bacteria. Eravacycline showed potent broad spectrum activity against 90% of the isolates (MIC₉₀) in each panel at concentrations ranging from ≤0.008 to 2 μg/mL for all species panels except Pseudomonas aeruginosa and Burkholderia cenocepacia (MIC₉₀ values of 32 μg/mL for both organisms). The antibacterial activity of eravacycline was minimally affected by expression of tetracycline-specific efflux and ribosomal protection mechanisms in clinical isolates. Further, eravacycline was active against multidrug-resistant bacteria, including those expressing extended spectrum β-lactamases and mechanisms conferring resistance to other classes of antibiotics, including carbapenem resistance. Eravacycline has the potential to be a promising new IV/oral antibiotic for the empiric treatment of complicated hospital/healthcare infections and moderate-to-severe community-acquired infections.

Tetraphase’s lead product candidate, eravacycline, has also received an award from Biomedical Advanced Research and Development Authority (BARDA) that provides for funding  to develop eravacycline as a potential counter-measure to certain biothreat pathogens. It is worth up to USD 67 million.

Process R&D of Eravacycline: The First Fully Synthetic Fluorocycline in Clinical Development

Eravacycline (TP-434)

We are developing our lead product candidate, eravacycline, as a broad-spectrum intravenous and oral antibiotic for use as a first-line empiric monotherapy for the treatment of multi-drug resistant (MDR) infections, including MDR Gram-negative bacteria. We developed eravacycline using our proprietary chemistry technology. We completed a successful Phase 2 clinical trial of eravacycline with intravenous administration for the treatment of patients with complicated intra-abdominal infections (cIAI) and have initiated the Phase 3 clinical program.

Eravacycline is a novel, fully synthetic tetracycline antibiotic. We selected eravacycline for development from tetracycline derivatives that we generated using our proprietary chemistry technology on the basis of the following characteristics of the compound that we observed in in vitro studies of the compound:

• potent antibacterial activity against a broad spectrum of susceptible and multi-drug resistant bacteria, including Gram-negative, Gram-positive, atypical and anaerobic bacteria;
• potential to treat the majority of patients as a first-line empiric monotherapy with convenient dosing; and
• potential for intravenous-to-oral step-down therapy.

In in vitro studies, eravacycline has been highly active against emerging multi-drug resistant pathogens like Acinetobacter baumannii as well as clinically important species ofEnterobacteriaceae, including those isolates that produce ESBLs or are resistant to the carbapenem class of antibiotics, and anaerobes.

Based on in vitro studies we have completed, eravacycline shares a similar potency profile with carbapenems except that it more broadly covers Gram-positive pathogens like MRSA and enterococci, is active against carbapenem-resistant Gram-negative bacteria and unlike carbapenems like Primaxin and Merrem is not active against Pseudomanas aeruginosa. Eravacycline has demonstrated strong activity in vitro against Gram-positive pathogens, including both nosocomial and community-acquired methicillin susceptible or resistantStaphylococcus aureus strains, vancomycin susceptible or resistant Enterococcus faecium andEnterococcus faecalis, and penicillin susceptible or resistant strains of Streptococcus pneumoniae. In in vitro studies for cIAI, eravacycline consistently exhibited strong activity against enterococci and streptococci. One of the most frequently isolated anaerobic pathogens in cIAI, either as the sole pathogen or often in conjunction with another Gram-negative bacterium, is Bacteroides fragilis. In these studies eravacycline demonstrated activity against Bacteroides fragilis and a wide range of Gram-positive and Gram-negative anaerobes.

Key Differentiating Attributes of Eravacycline
The following key attributes of eravacycline, observed in clinical trials and preclinical studies of eravacycline, differentiate eravacycline from other antibiotics targeting multi-drug resistant infections, including multi-drug resistant Gram-negative infections. These attributes will make eravacycline a safe and effective treatment for cIAI, cUTI and other serious and life-threatening infections for which we may develop eravacycline, such as ABSSSI and acute bacterial pneumonias.

• Broad-spectrum activity against a wide variety of multi-drug resistant Gram-negative, Gram-positive and anaerobic bacteria. In our recently completed Phase 2 clinical trial of the intravenous formulation of eravacycline, eravacycline demonstrated a high cure rate against a wide variety of multi-drug resistant Gram-negative, Gram-positive and anaerobic bacteria. In addition, in in vitro studies eravacycline demonstrated potent antibacterial activity against Gram-negative bacteria, including E. coli; ESBL-producing Klebsiella pneumoniae; Acinetobacter baumannii; Gram-positive bacteria, including MSRA and vancomycin-resistant enterococcus, or VRE; and anaerobic pathogens. As a result of this broad-spectrum coverage, eravacycline has the potential to be used as a first-line empiric monotherapy for the treatment of cIAI, cUTI, ABSSSI, acute bacterial pneumonias and other serious and life-threatening infections.
• Favorable safety and tolerability profile. Eravacycline has been evaluated in more than 250 subjects in the Phase 1 and Phase 2 clinical trials that we have conducted. In these trials, eravacycline demonstrated a favorable safety and tolerability profile. In our recent Phase 2 clinical trial of eravacycline, no patients suffered any serious adverse events, and safety and tolerability were comparable to ertapenem, the control therapy in the trial. In addition, in the Phase 2 clinical trial, the rate at which gastrointestinal adverse events such as nausea and vomiting that occurred in the eravacycline arms was comparable to the rate of such events in the ertapenem arm of the trial.
• Convenient dosing regimen. In our recently completed Phase 2 clinical trial we dosed eravacycline once or twice a day as a monotherapy. Eravacycline will be able to be administered as a first-line empiric monotherapy with once- or twice-daily dosing, avoiding the need for complicated dosing regimens typical of multi-drug cocktails and the increased risk of negative drug-drug interactions inherent to multi-drug cocktails.
• Potential for convenient intravenous-to-oral step-down. In addition to the intravenous formulation of eravacycline, we are also developing an oral formulation of eravacycline. If successful, this oral formulation would enable patients who begin intravenous treatment with eravacycline in the hospital setting to transition to oral dosing of eravacycline either in hospital or upon patient discharge for convenient home-based care. The availability of both intravenous and oral administration and the oral step-down will reduce the length of a patient’s hospital stay and the overall cost of care.

Additionally, in February 2012, Tetraphase announced a contract award from the Biomedical Advanced Research and Development Authority (BARDA) worth up to $67 million for the development of eravacycline, from which Tetraphase may receive up to approximately $40 million in funding. The contract includes pre-clinical efficacy and toxicology studies; clinical studies; manufacturing activities; and associated regulatory activities to position the broad-spectrum antibiotic eravacycline as a potential empiric countermeasure for the treatment of inhalational disease caused by Bacillus anthracis, Francisella tularensis and Yersinia pestis.\

PAPER

Process research and development of the first fully synthetic broad spectrum 7-fluorotetracycline in clinical development is described. The process utilizes two key intermediates in a convergent approach. The key transformation is a Michael–Dieckmann reaction between a suitable substituted aromatic moiety and a key cyclohexenone derivative. Subsequent deprotection and acylation provide the desired active pharmaceutical ingredient in good overall yield.

Process R&D of Eravacycline: The First Fully Synthetic Fluorocycline in Clinical Development