1
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Tobisch S. Copper-catalysed electrophilic carboamination of terminal alkynes with benzyne looked at through the computational lens. Dalton Trans 2024; 53:8154-8167. [PMID: 38536069 DOI: 10.1039/d3dt04301k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2024]
Abstract
A detailed computational mechanistic study of the copper-catalysed three-component-type electrophilic carboamination of terminal alkynes with benzyne and an archetypal O-benzoylhydroxylamine electrophile is presented. Probing various plausible pathways for relevant elementary steps and scrutinising performance degradation pathways, with the aid of a reliable computational protocol applied to a realistic catalyst model combined with kinetic analysis, identified the pathways preferably traversed in productive catalysis. It entails rapid alkynylcupration of in situ generated benzyne to deliver the arylcopper nucleophile that undergoes amination with the O-benzoylhydroxylamine electrophile to afford copper benzoate. Umpolung-enabled electrophilic amination favours a multistep SN2-type oxidative addition/N-C bond-forming reductive elimination sequence involving a short-lived formal {P^P}CuIII carboxylate amido aryl intermediate. SN2-type displacement of the benzoate leaving group at the arylcopper nucleophile, which represents the catalyst resting state, is predicted to be the turnover limiting step. Alkynolysis transforms copper benzoate back to catalytically competent alkynylcopper. The computational probe of a wider range of substrates reveals that only severely ring-strained C6-arynes, C6-cycloalkynes and electron-deficient cyclopropenes featuring a highly reactive C≡C linkage could replace benzyne. Moreover, strict control of stationary benzyne concentration is indispensable for electrophilic carboamination to ever become achievable.
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Affiliation(s)
- Sven Tobisch
- University of St Andrews, School of Chemistry, Purdie Building, North Haugh, St Andrews, KY16 9ST, UK.
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2
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Flynn MB, Flynn JF, Palacios AM. Capitalizing on Hope: Questionable Marketing Approval and Pricing of a New ALS Drug. INTERNATIONAL JOURNAL OF SOCIAL DETERMINANTS OF HEALTH AND HEALTH SERVICES 2024:27551938241247778. [PMID: 38646691 DOI: 10.1177/27551938241247778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Regulatory agencies must balance patient demands to access new treatments for fatal diseases with limited treatment options while ensuring drug safety and efficacy. However, questionable U.S. regulatory actions resulted in the early approval of AMX0035 to treat amyotrophic lateral sclerosis (ALS) by reconvening advisory commissions to obtain positive decisions and designating the drug as a new molecular entity. Data from one randomized clinical trial suggests minimal delays in disease progression and longer survivability, but debate remains about the lack of confirmatory evidence of effectiveness owing to study limitations. A patient's decision-making process details the experience of using the drug, including perspectives on access, cost, effectiveness, and adverse effects. In line with the "nichebuster" business model, the drugmaker, Amylyx Pharmaceuticals, is charging US$158,000/year/patient and thus forecast to turn a profit on a drug with debatable clinical effectiveness prior to completing a Phase 3 trial. Early marketing approval, despite community demands, is unnecessary and may have reduced access because of the end of a compassionate use program, and the high price tag results in restricted coverage and high out-of-pocket costs. Also, the drug's key ingredients are available as a generic and a supplement.
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Affiliation(s)
- Matthew B Flynn
- Department of Political Science and International Studies, Georgia Southern University College of Behavioural and Social Sciences, Statesboro, GA, USA
| | | | - Ana M Palacios
- Department of Health Policy and Community Health, Georgia Southern University Jiann-Ping Hsu College of Public Health, Savannah, GA, USA
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3
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McVicker R, O’Boyle NM. Chirality of New Drug Approvals (2013-2022): Trends and Perspectives. J Med Chem 2024; 67:2305-2320. [PMID: 38344815 PMCID: PMC10895675 DOI: 10.1021/acs.jmedchem.3c02239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/18/2024] [Accepted: 01/24/2024] [Indexed: 02/23/2024]
Abstract
Many drugs are chiral with their chirality determining their biological interactions, safety, and efficacy. Since the 1980s, there has been a regulatory preference to bring single enantiomer to market. This perspective discusses trends related to chirality that have developed in the past decade (2013-2022) of new drug approvals. The EMA has not approved a racemate since 2016, while the average for the FDA is one per year from 2013 to 2022. These 10 include drugs which have been previously marketed elsewhere for several decades, analogues of pre-existing drugs, or drugs where the undefined stereocenter does not play a role in therapeutic activity. Two chiral switches were identified which were both combined with drug repurposing. This combination strategy has the potential to produce therapeutically valuable drugs in a faster time frame. Two class III atropisomers displaying axial chirality were approved between 2013 and 2022, one as a racemate and one as a single enantiomer.
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Affiliation(s)
- Rebecca
U. McVicker
- School
of Pharmacy and Pharmaceutical Sciences, Trinity Biomedical Sciences
Institute, Trinity College Dublin, 152−160 Pearse Street, Dublin 2, D02 R590, Ireland
- Gamlen
Tableting Ltd, 3 Stanton
Way, London SE26 5FU, United Kingdom
| | - Niamh M. O’Boyle
- School
of Pharmacy and Pharmaceutical Sciences, Trinity Biomedical Sciences
Institute, Trinity College Dublin, 152−160 Pearse Street, Dublin 2, D02 R590, Ireland
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4
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D’Acquarica I, Agranat I. The Quest for Secondary Pharmaceuticals: Drug Repurposing/Chiral-Switches Combination Strategy. ACS Pharmacol Transl Sci 2023; 6:201-219. [PMID: 36798472 PMCID: PMC9926527 DOI: 10.1021/acsptsci.2c00151] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Indexed: 01/19/2023]
Abstract
Drug repurposing toward new medical uses and chiral switches are elements of secondary pharmaceuticals. The drug repurposing and chiral-switches strategies have mostly been applied independently in drug discovery. Drug repurposing has peaked in the search for therapeutic treatments of the Coronavirus Disease 2019 pandemic, whereas chiral switches have been overlooked. The current Perspective introduces the drug repurposing/chiral-switches combination strategy, overviewing representative cases of chiral drugs that have undergone this combination: ketamine, flurbiprofen, fenfluramine, and milnacipran. The deuterium-enabled chiral switches of racemic thalidomide analogs, a variation of the repurposing/chiral-switch combination strategy, is also included. Patenting and regulatory-exclusivity considerations of the combination strategy in the discovery of new medical uses are considered. The proposed combination creates a new synergy of its two elements, overcoming arguments against chiral switches, with better prospects for validation of patents and regulatory exclusivities. The combination strategy may be applied to chiral switches to paired enantiomers. Repurposing/chiral-switch drugs may be 'obvious-to-try'; however, their inventions may be unexpected and their patents nonobvious. Patenting repurposing/chiral-switch combination drugs is not 'evergreening', 'product hopping', and 'me-too'. The expected benefits and opportunities of the combined repurposing/chiral-switch strategy vis-à-vis its two elements are superior pharmacological properties, overcoming arguments against patent validities, challenges of chiral-switch patents, reduced expenses, shortened approval procedures, and higher expectations of regulatory exclusivities.
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Affiliation(s)
- Ilaria D’Acquarica
- Dipartimento
di Chimica e Tecnologie del Farmaco, Sapienza
Università di Roma, 00185 Rome, Italy
| | - Israel Agranat
- Organic
Chemistry, Institute of Chemistry, The Hebrew
University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel
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5
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Blankart K, Naci H, Chandra A. Availability of New Medicines in the US and Germany From 2004 to 2018. JAMA Netw Open 2022; 5:e2229231. [PMID: 36040738 PMCID: PMC9428736 DOI: 10.1001/jamanetworkopen.2022.29231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
IMPORTANCE Germany's unique approach to coverage determination and pricing has ensured that effective medicines remain on the market, often at prices reduced through negotiation. However, less is known about trade-offs of this approach with regard to initial availability of medicines. OBJECTIVE To examine differences in the timing and scope of new medicines available in Germany and the US. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study analyzed initial availability of new medicines approved by regulatory agencies in Germany and the US between January 1, 2004, and December 31, 2018, and followed up through December 31, 2019. Data analysis was conducted from January 1, 2020, to July 1, 2022. A total of 599 novel approvals were reviewed. Generic, biosimilar, vaccine, and combination medicines were excluded. EXPOSURES US Food and Drug Administration approvals were reviewed for therapies categorized as new molecular entities or new active ingredients. German approvals were reviewed from secondary administrative data of authorized medicines that determine availability in Germany, including data presented by the European Medicines Agency. MAIN OUTCOMES AND MEASURES Approvals were analyzed to determine the percentage of medicines approved and available in the US, Germany, or both countries and compare the times to reach the market. RESULTS Analysis of 599 new medicines demonstrated that fewer were available in Germany compared with the US (80% vs 92% of all potential therapies) and that the median difference in time to market was 4 months (95% CI, -44.40 to 44.76 months). Forty-nine medicines were approved in Germany but not in the US, 75% of which were rejected by the US Food and Drug Administration, were withdrawn, or had US equivalent agents. CONCLUSIONS AND RELEVANCE In this cohort study, fewer new medicines were available in Germany compared with the US between 2004 and 2018. In addition, drugs entered the German market later than in the US.
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Affiliation(s)
- Katharina Blankart
- Faculty of Economics and Business Administration, University of Duisburg-Essen, Essen, Germany
| | - Huseyin Naci
- London School of Economics, London, United Kingdom
| | - Amitabh Chandra
- Harvard Kennedy School, Harvard University, Cambridge, Massachusetts
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6
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Bastia E, Sgambellone S, Lucarini L, Provensi G, Brambilla S, Galli C, Almirante N, Impagnatiello F. NCX 470 Restores Ocular Hemodynamics and Retinal Cell Physiology After ET-1-Induced Ischemia/Reperfusion Injury of Optic Nerve and Retina in Rabbits. J Ocul Pharmacol Ther 2022; 38:496-504. [PMID: 35787180 DOI: 10.1089/jop.2022.0004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Purpose: Determine whether NCX 470, a nitric oxide (NO)-donating bimatoprost with clinically demonstrated intraocular pressure (IOP)-lowering effects, improves ocular hemodynamics and retinal physiology. Methods: Endothelin-1 (ET-1)-induced ischemia/reperfusion model in New Zealand white rabbits was used. ET-1 was injected next to the optic nerve twice/week (Monday and Thursday) for 6 weeks. Starting on week 3, animals received NCX 470 (0.1% bid, 6 days/week Monday-Saturday) or vehicle until the end of ET-1 treatment. IOP, ophthalmic artery resistive index (OA-RI) and retina physiology (electroretinogram, ERG) were determined before dosing and at different times post-dosing. All measurements were taken on Mondays before the AM daily dosing (36 h treatment-free). Finally, oxidative stress markers were determined in dissected retina and iris/ciliary body of treated eyes. Results: Injection of ET-1 progressively increased IOP (20.7 ± 0.6, 24.9 ± 1.2, and 27.0 ± 0.6 mmHg at baseline, week 2 and 6, respectively) and OA-RI (0.30 ± 0.02, 0.39 ± 0.02, and 0.42 ± 0.03 at baseline, week 2 and 6, respectively) and reduced rods and/or cones response as indicated by changes in ERG amplitudes under different stimulating conditions. NCX 470 re-established baseline IOP (21.8 ± 1.0 mmHg), OA-RI (0.33 ± 0.02), and ERG amplitude by week 6 (mostly rod response, 0.01Dark_AVeh_6week = 32.2 ± 3.0 μV and 0.01Dark_ANCX470_6week 44.3 ± 4.5 μV; mostly cone response, 3.0Dark_AVeh_6week = 87.6 ± 10.1 μV and 3.0Dark_ANCX470_6week = 122.8 ± 11.4 μV; combined rod/cone response, 3.0Light_AVeh_6week = 49.8 ± 6.5 μV and 3.0Light_ANCX470_6week = 64.2 ± 6.8 μV). NCX 470 also reversed ET-1-induced changes in glutathione and manganese superoxide dismutase (oxidative stress markers) in retina and iris/ciliary body. Conclusions: Repeated ocular topical dosing with NCX 470 reverses ET-1-induced changes in IOP, OA-RI, and ERG suggesting improved ocular hemodynamics and retinal physiology likely independently from its demonstrated IOP-lowering effect.
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Affiliation(s)
| | - Silvia Sgambellone
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Florence, Italy
| | - Laura Lucarini
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Florence, Italy
| | - Gustavo Provensi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Florence, Italy
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7
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Hancu G, Modroiu A. Chiral Switch: Between Therapeutical Benefit and Marketing Strategy. Pharmaceuticals (Basel) 2022; 15:ph15020240. [PMID: 35215352 PMCID: PMC8877306 DOI: 10.3390/ph15020240] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/13/2022] [Accepted: 02/16/2022] [Indexed: 11/16/2022] Open
Abstract
Chirality of pharmaceutical substances is an important aspect in drug research because it determines how enantiomers will interact with chiral biological targets. Enantiomers of a chiral drug can have different pharmacokinetic and pharmacological profiles; consequently, using a single pure enantiomer instead of a racemate can enhance the effectiveness and/or safety of the treatment. The tendencies of modern pharmaceutical industry regarding the current market of chiral drugs are divided between the chiral switch of previously used racemates and the development of new enantiopure drugs. The term chiral switch refers to the replacement on the market of a previously approved racemate with its single enantiomer version. The potential advantages of chiral switch can be related to a higher therapeutic index due to better potency, selectivity and fewer adverse effects, faster onset of action and exposure of the patient to lower drug dosages. However, chiral switch is also a strategy that permits manufacturers to keep market exclusivity for chiral pharmaceuticals that have lost their patent protection, even if the pure enantiomers have not demonstrated higher effectiveness or safety profile compared with the racemates.
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8
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Gaudelet T, Day B, Jamasb AR, Soman J, Regep C, Liu G, Hayter JBR, Vickers R, Roberts C, Tang J, Roblin D, Blundell TL, Bronstein MM, Taylor-King JP. Utilizing graph machine learning within drug discovery and development. Brief Bioinform 2021; 22:bbab159. [PMID: 34013350 PMCID: PMC8574649 DOI: 10.1093/bib/bbab159] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 04/01/2021] [Accepted: 04/05/2021] [Indexed: 12/15/2022] Open
Abstract
Graph machine learning (GML) is receiving growing interest within the pharmaceutical and biotechnology industries for its ability to model biomolecular structures, the functional relationships between them, and integrate multi-omic datasets - amongst other data types. Herein, we present a multidisciplinary academic-industrial review of the topic within the context of drug discovery and development. After introducing key terms and modelling approaches, we move chronologically through the drug development pipeline to identify and summarize work incorporating: target identification, design of small molecules and biologics, and drug repurposing. Whilst the field is still emerging, key milestones including repurposed drugs entering in vivo studies, suggest GML will become a modelling framework of choice within biomedical machine learning.
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Affiliation(s)
| | - Ben Day
- Relation Therapeutics, London, UK
- The Computer Laboratory, University of Cambridge, UK
| | - Arian R Jamasb
- Relation Therapeutics, London, UK
- The Computer Laboratory, University of Cambridge, UK
- Department of Biochemistry, University of Cambridge, UK
| | | | | | | | | | | | | | - Jian Tang
- Mila, the Quebec AI Institute, Canada
- HEC Montreal, Canada
| | - David Roblin
- Relation Therapeutics, London, UK
- Juvenescence, London, UK
- The Francis Crick Institute, London, UK
| | | | - Michael M Bronstein
- Relation Therapeutics, London, UK
- Department of Computing, Imperial College London, UK
- Twitter, UK
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9
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Begley CG, Ashton M, Baell J, Bettess M, Brown MP, Carter B, Charman WN, Davis C, Fisher S, Frazer I, Gautam A, Jennings MP, Kearney P, Keeffe E, Kelly D, Lopez AF, McGuckin M, Parker MW, Rayner C, Roberts B, Rush JS, Sullivan M. Drug repurposing: Misconceptions, challenges, and opportunities for academic researchers. Sci Transl Med 2021; 13:eabd5524. [PMID: 34550729 DOI: 10.1126/scitranslmed.abd5524] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
[Figure: see text].
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Affiliation(s)
| | - Mark Ashton
- UniQuest Pty Ltd., University of Queensland, Brisbane, Queensland, Australia
| | - Jonathan Baell
- Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | | | - Michael P Brown
- Cancer Clinical Trials Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Brett Carter
- Bioseer Pty Ltd., Glen Iris, Victoria, Australia
| | - William N Charman
- Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Christopher Davis
- Institute for Glycomics, Griffith University, Gold Coast campus, Queensland, Australia
| | - Simon Fisher
- Novartis Pharmaceuticals Australia Pty Ltd., Macquarie Park, New South Wales, Australia
| | - Ian Frazer
- University of Queensland Diamantina Institute, Woolloongabba, Queensland, Australia
| | | | - Michael P Jennings
- Institute for Glycomics, Griffith University, Gold Coast campus, Queensland, Australia
| | - Philip Kearney
- Merck Sharp & Dohme, Macquarie Park, New South Wales, Australia
| | - Eloise Keeffe
- Institute for Glycomics, Griffith University, Gold Coast campus, Queensland, Australia
| | - Darren Kelly
- Department of Medicine, University of Melbourne, Parkville, Victoria, Australia
| | - Angel F Lopez
- Centre for Cancer Biology, Adelaide, South Australia, Australia
| | | | - Michael W Parker
- Bio21 Molecular Science and Biotechnology Institute, Parkville, Victoria, Australia
| | | | - Brett Roberts
- Novartis Pharmaceuticals Australia Pty Ltd., Macquarie Park, New South Wales, Australia
| | | | - Mark Sullivan
- Medicines Development for Global Health, Southbank, Victoria, Australia
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10
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Long AS, Zhang AD, Meyer CE, Egilman AC, Ross JS, Wallach JD. Evaluation of Trials Comparing Single-Enantiomer Drugs to Their Racemic Precursors: A Systematic Review. JAMA Netw Open 2021; 4:e215731. [PMID: 33956134 PMCID: PMC8103227 DOI: 10.1001/jamanetworkopen.2021.5731] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
IMPORTANCE Chiral switching, a strategy in which drug manufacturers develop a single-enantiomer formulation of a drug to be substituted for a racemic formulation, allows manufacturers to maintain market exclusivity for drugs losing patent protection, even without demonstrating superior efficacy or safety. OBJECTIVE To identify and characterize all randomized clinical trials (RCTs) directly comparing a Food and Drug Administration (FDA)-approved single-enantiomer drug against a previously approved racemic drug for 1 or more efficacy or safety end points. EVIDENCE REVIEW Drugs were identified using the Drugs@FDA database. Randomized clinical trials were identified using Ovid MEDLINE (1949 to October 22, 2019), Ovid Embase (1974 to October 22, 2019), Web of Science Core Collection (all years), ClinicalTrials.gov, and Cochrane Central Registry of Controlled Trials (CENTRAL, Wiley, Issue 8 of 12, October 22, 2019). Trials were characterized as favoring the single-enantiomer or racemic drugs based on whether the primary efficacy, secondary efficacy, and safety end points achieved each study's defined significance level (eg, P < .05). Trials were characterized as favoring neither drug if no statistically significant differences were reported for any end point or if both drugs were found to be superior for 1 or more separate end points. FINDINGS Fifteen FDA-approved single-enantiomer drugs were identified with racemic precursors approved in the US or Europe. For 3 single-enantiomer racemic drug pairs, no RCTs directly comparing the drugs were identified. For the remaining 12 pairs, 185 RCTs comparing efficacy or safety of the drug pairs were identified, 124 (67.0%) of which studied 1 pair (levobupivacaine/bupivacaine). There were 179 RCTs directly comparing drug pairs using efficacy end points, of which 23 (12.8%) favored the single enantiomer based on primary efficacy end point results. There were 124 RCTs directly comparing drug pairs using safety end points, of which 17 (13.7%) favored the single-enantiomer drug. For 9 of the 15 single-enantiomer drugs (60.0%), no RCTs were identified providing evidence of improved efficacy, based on primary end point results, or safety as compared with their racemic precursors. CONCLUSIONS AND RELEVANCE The results of this systematic review suggest that most newly marketed FDA-approved single-enantiomer drugs are infrequently directly compared with their racemic precursors, and when compared, they are uncommonly found to provide improved efficacy or safety, despite their greater costs.
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Affiliation(s)
- Aaron S. Long
- Yale University School of Medicine, New Haven, Connecticut
| | | | - Caitlin E. Meyer
- Harvey Cushing/John Hay Whitney Medical Library, Yale University, New Haven, Connecticut
| | | | - Joseph S. Ross
- Center for Outcomes Research and Evaluation, New Haven, Connecticut
- Section of General Internal Medicine, Yale School of Medicine, New Haven, Connecticut
- National Clinician Scholars Program, Yale School of Medicine, Department of Internal Medicine, New Haven, Connecticut
- Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut
| | - Joshua D. Wallach
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, Connecticut
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11
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Smajlagic I, Carlson B, Dudding T. Brønsted Acid Organocatalyzed Three-Component Hydroamidation Reactions of Vinyl Ethers. J Org Chem 2021; 86:4171-4181. [PMID: 33626274 DOI: 10.1021/acs.joc.0c03017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydroamidation of carbon-carbon double bonds is an attractive strategy for installing nitrogen functionality into molecular scaffolds and, with it, increasing molecular complexity. To date, metal-based approaches have dominated this area of chemical synthesis, despite the drawbacks of air and moisture sensitivity, limited functional group tolerance, toxicity, and/or high cost often associated with using metals. Here, in offering an alternative solution, we disclose an operationally simple, metal-free, one-pot, regioselective, multicomponent synthetic procedure for the hydroamidation of carbon-carbon double bonds. This method features mild reaction conditions and utilizes isocyanides and vinyl ethers for the rapid and modular synthesis of privileged α-oxygenated amide scaffolds. In unraveling the mechanistic underpinning of this non-metal-based reactivity, we present kinetic solvent isotope effect studies, variable time normalization analysis, and density functional theory computations offering insight into the mechanism of this multistep catalytic hydroamidation process.
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Affiliation(s)
- Ivor Smajlagic
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada
| | - Brenden Carlson
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada
| | - Travis Dudding
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada
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12
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Bastia E, Toris CB, Brambilla S, Galli C, Almirante N, Bergamini MVW, Masini E, Sgambellone S, Unser AM, Ahmed F, Torrejon KY, Navratil T, Impagnatiello F. NCX 667, a Novel Nitric Oxide Donor, Lowers Intraocular Pressure in Rabbits, Dogs, and Non-Human Primates and Enhances TGFβ2-Induced Outflow in HTM/HSC Constructs. Invest Ophthalmol Vis Sci 2021; 62:17. [PMID: 33704360 PMCID: PMC7960798 DOI: 10.1167/iovs.62.3.17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Purpose NCX 667, a novel nitric oxide (NO) donor with an isomannide core, was characterized for its IOP-lowering ability in animal models of ocular hypertension and glaucoma. Bioengineered human trabecular meshwork/Schlemm's canal (HTM/HSC) constructs were used to explore the mode of action. Methods Ocular normotensive New Zealand white (NZW) rabbits (ONT-rabbits), spontaneously ocular hypertensive pigmented Dutch-belted rabbits (sOHT-rabbits), hypertonic saline (5%)–induced transient ocular hypertensive NZW rabbits (tOHT-rabbits), ocular normotensive Beagle dogs (ONT-dogs), and laser-induced ocular hypertensive cynomolgus monkeys (OHT-monkeys) were used. NCX 667 or vehicle (30 µL) was instilled in a crossover, masked fashion and intraocular pressure (IOP) measured before dosing (baseline) and for several hours thereafter. The ONT-rabbits were used for cyclic guanosine monophosphate (cGMP) determination in ocular tissues after ocular dosing with NCX 667. Transforming growth factor-beta2 (TGFβ2) (2.5 ng/mL, six days)–treated HTM/HSC constructs were used to address changes in outflow facility. Results NCX 667 resulted in robust and dose-dependent IOP decrease in all models used. Maximal IOP-lowering efficacy at 1% was −4.1 ± 0.6, −12.2 ± 2.7, −10.5 ± 2.0, −5.3 ± 0.8, and −6.6 ± 1.9 mmHg, respectively, in ONT-dogs, sOHT-rabbits, tOHT-rabbits, ONT-rabbits, and OHT-monkeys. In ONT-rabbits NCX 667 (1%) increased cGMP in aqueous humor (AH) but not in retina and iris/ciliary body. NCX 667 concentration-dependently increased outflow facility in TGFβ2-treated HTM/HSC constructs (outflow facility, 0.10 ± 0.06 and 0.30 ± 0.10 µL/min/mmHg/mm2, respectively, in vehicle- and NCX 667–treated constructs). Conclusions NCX 667 leads to robust IOP lowering in several animal models. Evidence in HTM/HSC constructs indicate that the IOP reduction likely results from NO-mediated increase of the conventional outflow pathway. Other mechanisms including changes in AH production and episcleral vein pressure may not be excluded at this time.
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Affiliation(s)
| | - Carol B Toris
- University of Nebraska Medical Center, Omaha, Nebraska, United States
| | | | | | | | - Michael V W Bergamini
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Emanuela Masini
- Department of NEUROFARBA, Section of Pharmacology, University of Florence, Florence, Italy
| | - Silvia Sgambellone
- Department of NEUROFARBA, Section of Pharmacology, University of Florence, Florence, Italy
| | - Andrea M Unser
- Glauconicx Biosciences Inc., Albany, New York, Unites States
| | - Feryan Ahmed
- Glauconicx Biosciences Inc., Albany, New York, Unites States
| | | | - Tomas Navratil
- Nicox Ophthalmics, Inc., Durham, North Carolina, United States
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14
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Wills TJ, Lipkus AH. Structural Approach to Assessing the Innovativeness of New Drugs Finds Accelerating Rate of Innovation. ACS Med Chem Lett 2020; 11:2114-2119. [PMID: 33209190 PMCID: PMC7667644 DOI: 10.1021/acsmedchemlett.0c00319] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/10/2020] [Indexed: 01/15/2023] Open
Abstract
![]()
Measuring innovation
in the pharmaceutical industry is challenging.
Counts of new molecular entities (NMEs) approved by the Food and Drug
Administration (FDA) are commonly used, but this measure only gauges
quantity not innovativeness. A new indicator of innovation for small
molecule and peptide drugs based on structural novelty is proposed
and used to analyze recent trends in pharmaceutical innovation. We
show pharmaceutical innovation has significantly increased over the
last several decades despite recent concerns over an innovation crisis
and find Pioneers (a NME whose shape and scaffold were not used in
any previously FDA-approved drugs) are significantly more likely to
be the source of promising new therapies. Analysis of the underlying
source of structural innovation indicates that scaffolds first reported
in the CAS REGISTRY five or less years prior to their Investigational
New Drug application (IND) or on scaffolds populated with 50 or less
other compounds at the time of IND tend to be the main source of Pioneers.
Our analysis also shows a widening structural innovation gap between
large pharmaceutical companies (Big Pharma) and the rest of the ecosystem
even though the number of Big Pharma originated Pioneers has increased.
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Affiliation(s)
- Todd J. Wills
- CAS, P.O. Box 3012, Columbus, Ohio 43210-0012, United States
| | - Alan H. Lipkus
- CAS, P.O. Box 3012, Columbus, Ohio 43210-0012, United States
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15
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Lodochnikova OA, Akhmetshina EA, Mingaleva ER, Startseva VA, Litvinov IA, Plemenkov VV, Nikitina LE. Stable and reproducible supramolecular motif in the crystal structure of sulfonamides of the benzothiazine series fused to an epoxybornane moiety. Russ Chem Bull 2020. [DOI: 10.1007/s11172-020-2762-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Tobisch S. Copper hydride-mediated electrophilic amidation of vinylarenes with dioxazolones - a computational mechanistic study. Dalton Trans 2019; 48:14337-14346. [PMID: 31490494 DOI: 10.1039/c9dt02540e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A detailed computational mechanistic study of the CuH-catalysed formal hydroamidation of vinylarenes with dioxazolone and hydrosilane by a prototype (dppbz)CuH catalyst (dppbz ≡ {P^P} ≡ 1,2-bis(diphenylphosphino)benzene) is presented. Probing various plausible pathways for relevant elementary steps with the aid of a reliable computational protocol applied to a realistic catalyst model identified the pathways preferably traversed in productive catalysis. It entails hydrocupration exclusively generating the benzylcopper nucleophile that undergoes amidation with the dioxazolone electrophile to afford copper amidate. Umpolung electrophilic amidation favours a stepwise oxidative Cu[double bond, length as m-dash]N coupling with a simultaneous decarboxylation/C-N bond forming reductive elimination sequence. Copper amidate represents the catalyst resting state. Its conversion back into the catalytically active copper hydride upon transmetalation with hydrosilane involves fast nucleophilic attack followed by slow hydrogen atom transfer. Electron-poor styrenes accelerate the hydrocupration with a noticeably reduced barrier found for styrene featuring a para-CF3 substituted phenyl ring. On the other hand, transmetalation becomes faster the more electron-rich the oxazolone amidating agent is.
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Affiliation(s)
- Sven Tobisch
- University of St Andrews, School of Chemistry, Purdie Building, North Haugh, St Andrews, KY16 9ST, UK.
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17
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Zhou Y, Engl OD, Bandar JS, Chant ED, Buchwald SL. CuH-Catalyzed Asymmetric Hydroamidation of Vinylarenes. Angew Chem Int Ed Engl 2018; 57:6672-6675. [PMID: 29660768 PMCID: PMC5992098 DOI: 10.1002/anie.201802797] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Indexed: 11/10/2022]
Abstract
A CuH-catalyzed enantioselective hydroamidation reaction of vinylarenes has been developed using readily accessible 1,4,2-dioxazol-5-ones as electrophilic amidating reagents. This method provides a straightforward and efficient approach to synthesize chiral amides in good yields with high levels of enantiopurity under mild conditions. Moreover, this transformation tolerates substrates bearing a broad range of functional groups.
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Affiliation(s)
- Yujing Zhou
- Department of Chemistry, Room 18-490, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Oliver D Engl
- Department of Chemistry, Room 18-490, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Jeffrey S Bandar
- Department of Chemistry, Room 18-490, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Emma D Chant
- Department of Chemistry, Room 18-490, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Stephen L Buchwald
- Department of Chemistry, Room 18-490, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
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18
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Zhou Y, Engl OD, Bandar JS, Chant ED, Buchwald SL. CuH‐Catalyzed Asymmetric Hydroamidation of Vinylarenes. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201802797] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yujing Zhou
- Department of Chemistry, Room 18–490Massachusetts Institute of Technology Cambridge MA 02139 USA
| | - Oliver D. Engl
- Department of Chemistry, Room 18–490Massachusetts Institute of Technology Cambridge MA 02139 USA
| | - Jeffrey S. Bandar
- Department of Chemistry, Room 18–490Massachusetts Institute of Technology Cambridge MA 02139 USA
| | - Emma D. Chant
- Department of Chemistry, Room 18–490Massachusetts Institute of Technology Cambridge MA 02139 USA
| | - Stephen L. Buchwald
- Department of Chemistry, Room 18–490Massachusetts Institute of Technology Cambridge MA 02139 USA
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19
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Zaugg J, Gumulya Y, Bodén M, Mark AE, Malde AK. Effect of Binding on Enantioselectivity of Epoxide Hydrolase. J Chem Inf Model 2018; 58:630-640. [DOI: 10.1021/acs.jcim.7b00353] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Julian Zaugg
- School of Chemistry and Molecular Biosciences, University of Queensland, 4072 Brisbane, Australia
| | - Yosephine Gumulya
- School of Chemistry and Molecular Biosciences, University of Queensland, 4072 Brisbane, Australia
| | - Mikael Bodén
- School of Chemistry and Molecular Biosciences, University of Queensland, 4072 Brisbane, Australia
- Institute for Molecular Bioscience, University of Queensland, 4072 Brisbane, Australia
| | - Alan E. Mark
- School of Chemistry and Molecular Biosciences, University of Queensland, 4072 Brisbane, Australia
- Institute for Molecular Bioscience, University of Queensland, 4072 Brisbane, Australia
| | - Alpeshkumar K. Malde
- School of Chemistry and Molecular Biosciences, University of Queensland, 4072 Brisbane, Australia
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20
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Calcaterra A, D’Acquarica I. The market of chiral drugs: Chiral switches versus de novo enantiomerically pure compounds. J Pharm Biomed Anal 2018; 147:323-340. [DOI: 10.1016/j.jpba.2017.07.008] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/06/2017] [Accepted: 07/08/2017] [Indexed: 10/19/2022]
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21
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Learning epistatic interactions from sequence-activity data to predict enantioselectivity. J Comput Aided Mol Des 2017; 31:1085-1096. [DOI: 10.1007/s10822-017-0090-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 12/04/2017] [Indexed: 10/18/2022]
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22
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Sebastián-Pérez V, Roca C, Awale M, Reymond JL, Martinez A, Gil C, Campillo NE. Medicinal and Biological Chemistry (MBC) Library: An Efficient Source of New Hits. J Chem Inf Model 2017; 57:2143-2151. [PMID: 28813151 DOI: 10.1021/acs.jcim.7b00401] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Identification of new hits is one of the biggest challenges in drug discovery. Creating a library of well-characterized drug-like compounds is a key step in this process. Our group has developed an in-house chemical library called the Medicinal and Biological Chemistry (MBC) library. This collection has been successfully used to start several medicinal chemistry programs and developed in an accumulation of more than 30 years of experience in drug design and discovery of new drugs for unmet diseases. It contains over 1000 compounds, mainly heterocyclic scaffolds. In this work, analysis of drug-like properties and comparative study with well-known libraries by using different computer software are presented here.
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Affiliation(s)
- Víctor Sebastián-Pérez
- Centro de Investigaciones Biológicas (CIB, CSIC) , Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Carlos Roca
- Centro de Investigaciones Biológicas (CIB, CSIC) , Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Mahendra Awale
- Department of Chemistry and Biochemistry, University of Bern , Freiestrasse 3, 3012 Bern, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, University of Bern , Freiestrasse 3, 3012 Bern, Switzerland
| | - Ana Martinez
- Centro de Investigaciones Biológicas (CIB, CSIC) , Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Carmen Gil
- Centro de Investigaciones Biológicas (CIB, CSIC) , Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Nuria E Campillo
- Centro de Investigaciones Biológicas (CIB, CSIC) , Ramiro de Maeztu 9, 28040 Madrid, Spain
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23
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Magro L, Arzenton E, Moretti U, Sottosanti L, Potenza S, Leone R. Italian monitoring registries: a tool for a safer use of innovative drugs? Data from the national pharmacovigilance system. Expert Opin Drug Saf 2016; 15:69-75. [PMID: 27875920 DOI: 10.1080/14740338.2016.1248942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVES Our aim was to investigate the ADR reports of drugs with a monitoring registry (MR drugs), in particular those related to abuse/misuse, medication error, overdose, which might indicate an unsafe use. We compared these reports with those of similar drugs without a registry (non-MR drugs), thus verifying whether the registries could be useful tools for a safer use of innovative drugs. METHODS All ADR reports included in the Italian Pharmacovigilance Network database from January 1st 2013 to December 31st 2015 (vaccines and literature cases excluded) were analysed. We compared the ADR reports of MR and non-MR drugs with the same ATC class at III level. RESULTS The percentage of ADR reports with a completed 'Section 7' was significantly lower for MR compared to non-MR drugs (2.0 versus 6.2, p < 0.001). The difference concerned in particular the ADR reports related to abuse/misuse, medication errors and overdose. These reports, more strictly related to inappropriate use, were less frequent for MR drugs in all the considered ATC classes. CONCLUSIONS Our study suggests that monitoring registries could be a useful tool for the reduction of frequency of ADRs related to inappropriate use, besides the control of pharmaceutical budget.
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Affiliation(s)
- Lara Magro
- a Department of Diagnostics and Public Health, Section of Pharmacology , University of Verona , Verona , Italy
| | - Elena Arzenton
- a Department of Diagnostics and Public Health, Section of Pharmacology , University of Verona , Verona , Italy
| | - Ugo Moretti
- a Department of Diagnostics and Public Health, Section of Pharmacology , University of Verona , Verona , Italy
| | - Laura Sottosanti
- b Italian Medicines Agency , Pharmacovigilance Office , Rome , Italy
| | - Simona Potenza
- b Italian Medicines Agency , Pharmacovigilance Office , Rome , Italy
| | - Roberto Leone
- a Department of Diagnostics and Public Health, Section of Pharmacology , University of Verona , Verona , Italy
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24
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Knight-Schrijver V, Chelliah V, Cucurull-Sanchez L, Le Novère N. The promises of quantitative systems pharmacology modelling for drug development. Comput Struct Biotechnol J 2016; 14:363-370. [PMID: 27761201 PMCID: PMC5064996 DOI: 10.1016/j.csbj.2016.09.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/08/2016] [Accepted: 09/19/2016] [Indexed: 01/01/2023] Open
Abstract
Recent growth in annual new therapeutic entity (NTE) approvals by the U.S. Food and Drug Administration (FDA) suggests a positive trend in current research and development (R&D) output. Prior to this, the cost of each NTE was considered to be rising exponentially, with compound failure occurring mainly in clinical phases. Quantitative systems pharmacology (QSP) modelling, as an additional tool in the drug discovery arsenal, aims to further reduce NTE costs and improve drug development success. Through in silico mathematical modelling, QSP can simulate drug activity as perturbations in biological systems and thus understand the fundamental interactions which drive disease pathology, compound pharmacology and patient response. Here we review QSP, pharmacometrics and systems biology models with respect to the diseases covered as well as their clinical relevance and applications. Overall, the majority of modelling focus was aligned with the priority of drug-discovery and clinical trials. However, a few clinically important disease categories, such as Immune System Diseases and Respiratory Tract Diseases, were poorly covered by computational models. This suggests a possible disconnect between clinical and modelling agendas. As a standard element of the drug discovery pipeline the uptake of QSP might help to increase the efficiency of drug development across all therapeutic indications.
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Affiliation(s)
| | - V. Chelliah
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | | | - N. Le Novère
- Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
- Corresponding author.
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25
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Hua F, Yiping Z, Quanling X, Xiaoyan H, Zhuan H. Syntheses and biological evaluation of phosphoryl-containing polyunsaturated fatty acid derivatives as hypolipidemic agents. PHOSPHORUS SULFUR 2016. [DOI: 10.1080/10426507.2016.1146275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Fang Hua
- The Third Institute of Oceanography of the State Oceanic Administration, Xiamen, People's Republic of China
| | - Zhang Yiping
- The Third Institute of Oceanography of the State Oceanic Administration, Xiamen, People's Republic of China
| | - Xie Quanling
- The Third Institute of Oceanography of the State Oceanic Administration, Xiamen, People's Republic of China
| | - Huang Xiaoyan
- The Third Institute of Oceanography of the State Oceanic Administration, Xiamen, People's Republic of China
| | - Hong Zhuan
- The Third Institute of Oceanography of the State Oceanic Administration, Xiamen, People's Republic of China
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26
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Michman E, Agranat I. Classroom Enters the Courtroom: Stereochemistry of SN1 and SN2 Reactions in Enantiomer Patent Litigations of the Antidepressant Escitalopram. Chirality 2015; 28:39-43. [PMID: 26477341 DOI: 10.1002/chir.22501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/19/2015] [Indexed: 11/07/2022]
Abstract
The role of elementary stereochemistry is illustrated in the patent litigations of the blockbuster antidepressant drug escitalopram oxalate. An undergraduate student of organic chemistry would recognize the stereochemical courses of the intramolecular SN 2 and SN 1 reactions of the single-enantiomer (S)-diol intermediate in the synthesis of the blockbuster antidepressant drug escitalopram oxalate: retention of configuration of the chiral carbon atom under basic conditions and racemization under acidic conditions, respectively. He/she, in searching for a stereoselective ring-closure reaction of the enantiomeric diol, will think of an SN 2 reaction in a basic medium. From these points of view, the process claim in the enantiomer patents of escitalopram is obvious/lacks an inventive step. An organic chemistry examination problem based on this scenario is offered.
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Affiliation(s)
- Elisheva Michman
- Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Israel Agranat
- Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
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