1
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Poudel YB, He L, Cox M, Zhang Q, Johnson WL, Cong Q, Cheng H, Chowdari NS, Tarby C, Donnell AF, Broekema M, O’Malley DP, Zhang Y, A. M. Subbaiah M, Kumar BV, Subramani L, Wang B, Li YX, Sivaprakasam P, Critton D, Mulligan D, Sandhu B, Xie C, Ramakrishnan R, Nagar J, Dudhgaonkar S, Oderinde MS, Murtaza A, Schieven GL, Mathur A, Gavai AV, Vite G, Gangwar S. Discovery of Novel TLR7 Agonists as Systemic Agent for Combination With aPD1 for Use in Immuno-oncology. ACS Med Chem Lett 2024; 15:181-188. [PMID: 38352830 PMCID: PMC10860183 DOI: 10.1021/acsmedchemlett.3c00455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 01/03/2024] [Accepted: 01/03/2024] [Indexed: 02/16/2024] Open
Abstract
We have designed and developed novel and selective TLR7 agonists that exhibited potent receptor activity in a cell-based reporter assay. In vitro, these agonists significantly induced secretion of cytokines IL-6, IL-1β, IL-10, TNFa, IFNa, and IP-10 in human and mouse whole blood. Pharmacokinetic and pharmacodynamic studies in mice showed a significant secretion of IFNα and TNFα cytokines. When combined with aPD1 in a CT-26 tumor model, the lead compound showed strong synergistic antitumor activity with complete tumor regression in 8/10 mice dosed using the intravenous route. Structure-activity relationship studies enabled by structure-based designs of TLR7 agonists are disclosed.
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Affiliation(s)
- Yam B. Poudel
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Liqi He
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Matthew Cox
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Qian Zhang
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Walter L. Johnson
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Qiang Cong
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Heng Cheng
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Naidu S. Chowdari
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Christine Tarby
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Andrew F. Donnell
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Matthais Broekema
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Daniel P. O’Malley
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Yong Zhang
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | | | - Boda Vijay Kumar
- The
Biocon Bristol Myers Squibb Research Center (BBRC), Bangalore 560099, India
| | | | - Bei Wang
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Yi-Xin Li
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Prasanna Sivaprakasam
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - David Critton
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Dawn Mulligan
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Bhupindar Sandhu
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Chunshan Xie
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Radha Ramakrishnan
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Jignesh Nagar
- The
Biocon Bristol Myers Squibb Research Center (BBRC), Bangalore 560099, India
| | | | - Martins S. Oderinde
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Anwar Murtaza
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Gary L. Schieven
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Arvind Mathur
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Ashvinikumar V. Gavai
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Gregory Vite
- Bristol-Myers
Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Sanjeev Gangwar
- Bristol-Myers
Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
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2
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Sivaprakasam P, McDonald I, Iwuagwu C, Chowdari NS, Peese KM, Langley DR, Cheng H, Luzung MR, Schmidt MA, Zheng B, Tan Y, Cho P, Rakshit S, Lakshminarasimhan T, Guturi S, Kanagavel K, Kanusu U, Niyogi AG, Sidhar S, Vaidyanathan R, Eastgate MD, Kotapati S, Deshpande M, Pan C, Cardarelli PM, Xie C, Rao C, Holder P, Sarma G, Vite G, Gangwar S. DNA-Model-Based Design and Execution of Some Fused Benzodiazepine Hybrid Payloads for Antibody-Drug Conjugate Modality. ACS Med Chem Lett 2021; 12:404-412. [PMID: 33738068 DOI: 10.1021/acsmedchemlett.0c00578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 01/27/2021] [Indexed: 11/28/2022] Open
Abstract
A new series with the tetrahydroisoquinoline-fused benzodiazepine (TBD) ring system combined with the surrogates of (1-methyl-1H-pyrrol-3-yl)benzene ("MPB") payloads were designed and executed for conjugation with a monoclonal antibody for anticancer therapeutics. DNA models helped in rationally identifying modifications of the "MPB" binding component and guided structure-activity relationship generation. This hybrid series of payloads exhibited excellent in vitro activity when tested against a panel of various cancer cell lines. One of the payloads was appended with a lysosome-cleavable peptide linker and conjugated with an anti-mesothelin antibody via a site-specific conjugation method mediated by the enzyme bacterial transglutaminase (BTGase). Antibody-drug conjugate (ADC) 50 demonstrated good plasma stability and lysosomal cleavage. A single intravenous dose of ADC 50 (5 or 10 nmol/kg) showed robust efficacy in an N87 gastric cancer xenograft model.
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Affiliation(s)
- Prasanna Sivaprakasam
- Computer-Aided Drug Design, Bristol-Myers Squibb Research and Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Ivar McDonald
- Discovery Chemistry, Bristol-Myers Squibb Research and Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Christiana Iwuagwu
- Discovery Chemistry, Bristol-Myers Squibb Research and Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Naidu S. Chowdari
- Discovery Chemistry, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Kevin M. Peese
- Discovery Chemistry, Bristol-Myers Squibb Research and Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - David R. Langley
- Computer-Aided Drug Design, Bristol-Myers Squibb Research and Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Heng Cheng
- Discovery Chemistry, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Michael R. Luzung
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Michael A. Schmidt
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Bin Zheng
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Yichen Tan
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Patricia Cho
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Souvik Rakshit
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Thirumalai Lakshminarasimhan
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Sivakrishna Guturi
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Kishorekumar Kanagavel
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Umamaheswararao Kanusu
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Ankita G. Niyogi
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Somprabha Sidhar
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Rajappa Vaidyanathan
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Martin D. Eastgate
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Srikanth Kotapati
- Discovery Biotherapeutics, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Madhura Deshpande
- Discovery Biotherapeutics, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Chin Pan
- Cell Biology and Pharmacology, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Pina M. Cardarelli
- Cell Biology and Pharmacology, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Chunshan Xie
- Lead Discovery and Optimization, Bristol-Myers Squibb Research and Development, P.O.
Box 4000, Princeton, New Jersey 08543, United States
| | - Chetana Rao
- Discovery Biotherapeutics, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Patrick Holder
- Discovery Biotherapeutics, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Ganapathy Sarma
- Discovery Biotherapeutics, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Gregory Vite
- Discovery Chemistry, Bristol-Myers Squibb Research and Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Sanjeev Gangwar
- Discovery Chemistry, Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
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3
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Poudel YB, Chowdari NS, Cheng H, Iwuagwu CI, King HD, Kotapati S, Passmore D, Rampulla R, Mathur A, Vite G, Gangwar S. Chemical Modification of Linkers Provides Stable Linker-Payloads for the Generation of Antibody-Drug Conjugates. ACS Med Chem Lett 2020; 11:2190-2194. [PMID: 33214828 DOI: 10.1021/acsmedchemlett.0c00325] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 09/22/2020] [Indexed: 12/22/2022] Open
Abstract
Stability of antibody-drug conjugates (ADCs) in mouse serum is one of the critical requirements for the evaluation of ADCs in mouse tumor models. Described herein is a strategy to address the mouse serum instability of uncialamycin linker-payloads through various chemical approaches that involve modification of different parts of the linker and payload. This effort ultimately led to the identification of a m-amide p-aminobenzyl carbamate (MA-PABC) group that resulted in linkers with dramatic improvement of mouse serum stability without affecting the desired proteolytic cleavage.
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Affiliation(s)
- Yam B. Poudel
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Naidu S. Chowdari
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Heng Cheng
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Christiana I. Iwuagwu
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - H. Dalton King
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Srikanth Kotapati
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - David Passmore
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Richard Rampulla
- Bristol-Myers Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Arvind Mathur
- Bristol-Myers Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Gregory Vite
- Bristol-Myers Squibb Research & Development, Princeton, New Jersey 08543, United States
| | - Sanjeev Gangwar
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
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4
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Chowdari NS, Zhang Y, McDonald I, Johnson W, Langley DR, Sivaprakasam P, Mate R, Huynh T, Kotapati S, Deshpande M, Pan C, Menezes D, Wang Y, Rao C, Sarma G, Warrack BM, Rangan VS, Mei-Chen S, Cardarelli P, Deshpande S, Passmore D, Rampulla R, Mathur A, Borzilleri R, Rajpal A, Vite G, Gangwar S. Design, Synthesis, and Structure-Activity Relationships of Novel Tetrahydroisoquinolino Benzodiazepine Dimer Antitumor Agents and Their Application in Antibody-Drug Conjugates. J Med Chem 2020; 63:13913-13950. [PMID: 33155811 DOI: 10.1021/acs.jmedchem.0c01385] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A series of tetrahydroisoquinoline-based benzodiazepine dimers were synthesized and tested for in vitro cytotoxicity against a panel of cancer cell lines. Structure-activity relationship investigation of various spacers guided by molecular modeling studies helped to identify compounds with picomolar activity. Payload 17 was conjugated to anti-mesothelin and anti-fucosylated monosialotetrahexosylganglioside (FucGM1) antibodies using lysosome-cleavable valine-citrulline dipeptide linkers via heterogeneous lysine conjugation and bacterial transglutaminase-mediated site-specific conjugation. In vitro, these antibody drug conjugates (ADCs) exhibited significant cytotoxic and target-mediated selectivity on human cancer cell lines. The pharmacokinetics and efficacy of these ADCs were further evaluated in gastric and lung cancer xenograft models in mice. Consistent pharmacokinetic profiles, high target specificity, and robust antitumor activity were observed in these models after a single dose of the ADC-46 (0.02 μmol/kg).
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Affiliation(s)
- Naidu S Chowdari
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Yong Zhang
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Ivar McDonald
- Bristol Myers Squibb Research & Early Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Walter Johnson
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - David R Langley
- Bristol Myers Squibb Research & Early Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Prasanna Sivaprakasam
- Bristol Myers Squibb Research & Early Development, 5 Research Parkway, Wallingford, Connecticut 06492, United States
| | - Robert Mate
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Tram Huynh
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Srikanth Kotapati
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Madhura Deshpande
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Chin Pan
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Daniel Menezes
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Yichong Wang
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Chetana Rao
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Ganapathy Sarma
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Bethanne M Warrack
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Vangipuram S Rangan
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Sung Mei-Chen
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Pina Cardarelli
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Shrikant Deshpande
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - David Passmore
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Richard Rampulla
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Arvind Mathur
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Robert Borzilleri
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Arvind Rajpal
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Gregory Vite
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey 08543, United States
| | - Sanjeev Gangwar
- Bristol Myers Squibb Research & Early Development, 700 Bay Road, Redwood City, California 94063, United States
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5
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Gartshore C, Tadano S, Chanda PB, Sarkar A, Chowdari NS, Gangwar S, Zhang Q, Vite GD, Momirov J, Boger DL. Total Synthesis of Meayamycin and O-Acyl Analogues. Org Lett 2020; 22:8714-8719. [PMID: 33074680 DOI: 10.1021/acs.orglett.0c03308] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A short, scalable total synthesis of meayamycin is described by an approach that entails a longest linear sequence of 12 steps (22 steps overall) from commercially available chiral pool materials (ethyl l-lactate, BocNH-Thr-OH, and d-ribose) and introduces the most straightforward preparation of the right-hand subunit detailed to date. The use of the approach in the divergent synthesis of a representative series of O-acyl analogues is exemplified.
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Affiliation(s)
- Christopher Gartshore
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Shinji Tadano
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Prem B Chanda
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Anindya Sarkar
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Naidu S Chowdari
- Bristol Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Sanjeev Gangwar
- Bristol Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Qian Zhang
- Bristol Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Gregory D Vite
- Bristol Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States.,Bristol Myers Squibb Research & Development, P.O. Box 4000, Princeton, New Jersey 08543 United States
| | - Jelena Momirov
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L Boger
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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6
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Kotapati S, Passmore D, Yamazoe S, Sanku RKK, Cong Q, Poudel YB, Chowdari NS, Gangwar S, Rao C, Rangan VS, Cardarelli PM, Deshpande S, Strop P, Dollinger G, Rajpal A. Universal Affinity Capture Liquid Chromatography-Mass Spectrometry Assay for Evaluation of Biotransformation of Site-Specific Antibody Drug Conjugates in Preclinical Studies. Anal Chem 2019; 92:2065-2073. [DOI: 10.1021/acs.analchem.9b04572] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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7
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Chowdari NS, Pan C, Rao C, Langley DR, Sivaprakasam P, Sufi B, Derwin D, Wang Y, Kwok E, Passmore D, Rangan VS, Deshpande S, Cardarelli P, Vite G, Gangwar S. Uncialamycin as a novel payload for antibody drug conjugate (ADC) based targeted cancer therapy. Bioorg Med Chem Lett 2019; 29:466-470. [DOI: 10.1016/j.bmcl.2018.12.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/01/2018] [Accepted: 12/10/2018] [Indexed: 11/27/2022]
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8
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Nicolaou KC, Wang Y, Lu M, Mandal D, Pattanayak MR, Yu R, Shah AA, Chen JS, Zhang H, Crawford JJ, Pasunoori L, Poudel YB, Chowdari NS, Pan C, Nazeer A, Gangwar S, Vite G, Pitsinos EN. Streamlined Total Synthesis of Uncialamycin and Its Application to the Synthesis of Designed Analogues for Biological Investigations. J Am Chem Soc 2016; 138:8235-46. [DOI: 10.1021/jacs.6b04339] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K. C. Nicolaou
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yanping Wang
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
| | - Min Lu
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Debashis Mandal
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Manas R. Pattanayak
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Ruocheng Yu
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
| | - Akshay A. Shah
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
| | - Jason S. Chen
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Hongjun Zhang
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - James J. Crawford
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Laxman Pasunoori
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yam B. Poudel
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Naidu S. Chowdari
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Chin Pan
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Ayesha Nazeer
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Sanjeev Gangwar
- Bristol-Myers Squibb Research & Development, 700 Bay Road, Redwood City, California 94063, United States
| | - Gregory Vite
- Bristol-Myers Squibb Research & Development, Princeton, New Jersey 08543-4000, United States
| | - Emmanuel N. Pitsinos
- Department
of Chemistry, BioScience Research Collaborative, Rice University, 6100
Main Street, Houston, Texas 77005, United States
- Laboratory of Natural Products Synthesis & Bioorganic Chemistry, Institute of Nanoscience & Nanotechnology, National Centre of Scientific Research “Demokritos”, Agia Paraskevi GR-15310, Greece
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Chowdari NS, Ahmad M, Albertshofer K, Tanaka F, Barbas CF. Expedient Synthesis of Chiral 1,2- and 1,4-Diamines: Protecting Group Dependent Regioselectivity in Direct Organocatalytic Asymmetric Mannich Reactions. Org Lett 2006; 8:2839-42. [PMID: 16774270 DOI: 10.1021/ol060980d] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] Organocatalytic asymmetric Mannich reaction of protected amino ketones with imines in the presence of an L-proline-derived tetrazole catalyst afforded diamines with excellent yields and enantioselectivities of up to 99%. The amino ketone protecting group controlled the regioselectivity of the reaction providing access to chiral 1,2-diamines from azido ketones and 1,4-diamines from phthalimido ketones.
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Affiliation(s)
- Naidu S Chowdari
- The Skaggs Institute for Chemical Biology and the Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
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Abstract
A catalytic route for enantioselective total synthesis of cell adhesion inhibitor BIRT-377 is described. The quaternary stereocenter was constructed through l-proline-derived, tetrazole-catalyzed direct asymmetric alpha-amination of 3-(4-bromophenyl)-2-methylpropanal with dibenzyl azodicarboxylate. In the course of these studies, a one-pot trifluoro acetylation/selective benzyloxycarbonyl deprotection method was developed. [structure: see text]
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Affiliation(s)
- Naidu S Chowdari
- The Skaggs Institute for Chemical Biology The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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11
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Ramachary DB, Anebouselvy K, Chowdari NS, Barbas CF. Direct Organocatalytic Asymmetric Heterodomino Reactions: The Knoevenagel/Diels−Alder/Epimerization Sequence for the Highly Diastereoselective Synthesis of Symmetrical and Nonsymmetrical Synthons of Benzoannelated Centropolyquinanes. J Org Chem 2004; 69:5838-49. [PMID: 15373469 DOI: 10.1021/jo049581r] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Amino acids and amines have been used to catalyze three component hetero-domino Knoevenagel/Diels-Alder/epimerization reactions of readily available various precursor enones (1a-l), aldehydes (2a-p), and 1,3-indandione (3). The reaction provided excellent yields of highly substituted, symmetrical and nonsymmetrical spiro[cyclohexane-1,2'-indan]-1',3',4-triones (5) in a highly diastereoselective fashion with low to moderate enantioselectivity. The Knoevenagel condensation of arylaldehydes (2a-p) and 1,3-indandione (3) under organocatalysis provided arylidene-1,3-indandiones (17) in very good yields. We demonstrate for the first time amino acid- and amine-catalyzed epimerization reactions of trans-spiranes (6) to cis-spiranes (5). The mechanism of conversion of trans-spiranes (6) to cis-spiranes 5 was shown to proceed through a retro-Michael/Michael reaction rather than deprotonation/reprotonation by isolation of the morpholine enamine intermediate of cis-spirane (22). Prochiral cis-spiranes (5ab) and trans-spiranes (6ab) are excellent starting materials for the synthesis of benzoannelated centropolyquinanes. Under amino acid and amine catalysis, the topologically interesting dispirane 24 was prepared in moderate yields. Organocatalysis with pyrrolidine catalyzed a series of four reactions, namely the Michael/retro-Michael/Diels-Alder/epimerization reaction sequence to furnish cis-spirane 5ab in moderate yield from enone 1a and 1,3-indandione 3.
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Affiliation(s)
- D B Ramachary
- The Skaggs Institute for Chemical Biology and the Departments of Chemistry and Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
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12
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Chowdari NS, Suri JT, Barbas CF. Asymmetric Synthesis of Quaternary α- and β-Amino Acids and β-Lactams via Proline-Catalyzed Mannich Reactions with Branched Aldehyde Donors. Org Lett 2004; 6:2507-10. [PMID: 15255677 DOI: 10.1021/ol049248+] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] L-Proline-catalyzed direct asymmetric Mannich reactions of N-PMP protected alpha-imino ethyl glyoxylate with various alpha,alpha-disubstituted aldehydes affords quaternary beta-formyl alpha-amino acid derivatives with excellent yields and enantioselectivities. The Mannich products are further converted to the corresponding quaternary alpha- and beta-amino acids and beta-lactams.
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Affiliation(s)
- Naidu S Chowdari
- The Skaggs Institute for Chemical Biology and the Departments of Chemistry and Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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Notz W, Tanaka F, Watanabe SI, Chowdari NS, Turner JM, Thayumanavan R, Barbas CF. The direct organocatalytic asymmetric mannich reaction: unmodified aldehydes as nucleophiles. J Org Chem 2004; 68:9624-34. [PMID: 14656087 DOI: 10.1021/jo0347359] [Citation(s) in RCA: 240] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The unprecedented application of unmodified aldehydes as nucleophilic donors in direct catalytic asymmetric Mannich-type reactions is disclosed in a full account. Our efforts in broadening the applicability of chiral pyrrolidine-based catalysts in direct asymmetric Mannich-type reactions led to the highly diastereo- and enantioselective and concise synthesis of functionalized alpha- and beta-amino acids, beta-lactams, and amino alcohols.
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Affiliation(s)
- Wolfgang Notz
- The Skaggs Institute for Chemical Biology and the Departments of Chemistry and Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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15
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Ramachary DB, Chowdari NS, Barbas CF. Organocatalytic asymmetric domino knoevenagel/diels-alder reactions: a bioorganic approach to the diastereospecific and enantioselective construction of highly substituted spiro[5,5]undecane-1,5,9-triones. Angew Chem Int Ed Engl 2004; 42:4233-7. [PMID: 14502744 DOI: 10.1002/anie.200351916] [Citation(s) in RCA: 302] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- D B Ramachary
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Ramachary DB, Chowdari NS, Barbas CF. Organocatalytic Asymmetric Domino Knoevenagel/Diels–Alder Reactions: A Bioorganic Approach to the Diastereospecific and Enantioselective Construction of Highly Substituted Spiro[5,5]undecane-1,5,9-triones. Angew Chem Int Ed Engl 2003. [DOI: 10.1002/ange.200351916] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Chowdari NS, Ramachary DB, Barbas CF. Organocatalytic asymmetric assembly reactions: one-pot synthesis of functionalized beta-amino alcohols from aldehydes, ketones, and azodicarboxylates. Org Lett 2003; 5:1685-8. [PMID: 12735752 DOI: 10.1021/ol034333n] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] l-Proline catalyzed the enzyme-like direct asymmetric assembly of aldehydes, ketones, and azodicarboxylic acid esters to provide optically active beta-amino alcohols. This assembly reaction uses both aldehydes and ketones as donors in one pot. The aldol-derived stereocenter is formed with a reduced facial selectivity in reactions involving (R)-amino aldehydes. The reactions can be performed on a multigram scale under operationally simple and safe conditions without the requirement of an inert atmosphere or dry solvents.
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Affiliation(s)
- Naidu S Chowdari
- The Skaggs Institute for Chemical Biology and the Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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Choudary BM, Chowdari NS, Jyothi K, Kantam ML. Heterogeneous catalytic asymmetric aminohydroxylation of olefins using LDH-supported OsO4. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1169(02)00645-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Choudary BM, Chowdari NS, Madhi S, Kantam ML. A trifunctional catalyst for one-pot synthesis of chiral diols via Heck coupling-N-oxidation-asymmetric dihydroxylation: application for the synthesis of diltiazem and taxol side chain. J Org Chem 2003; 68:1736-46. [PMID: 12608786 DOI: 10.1021/jo026687i] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A heterogeneous bifunctional catalyst composed of OsO4(2-)-WO4(2-) and a trifunctional catalyst comprising PdCl4(2-)-OsO4(2-)-WO4(2-), designed and prepared by an ion-exchange technique using layered double hydroxides (LDH) as an ion-exchanger and their homogeneous bifunctional analogue, K2OsO4-Na2WO4 and trifunctional analogue, Na2PdCl4-K2OsO4-Na2WO4, devised for the first time are evaluated for the synthesis of chiral vicinal diols. These bifunctional and trifunctional catalysts perform asymmetric dihydroxylation-N-oxidation and Heck-asymmetric dihydroxylation-N-oxidation, respectively, in the presence of Sharpless chiral ligand, (DHQD)2PHAL in a single pot using H2O2 as a terminal oxidant to provide N-methylmorpholine oxide (NMO) in situ by the oxidation of N-methylmorpholine (NMM). The heterogeneous bifunctional catalyst supported on LDH (LDH-OsW) displays superior activity to afford diols with higher yields over the other heterogeneous catalysts developed by the ion exchange on quaternary ammonium salts covalently bound to resin (resin-OsW) and silica (silica-OsW) or homogeneous catalysts in the achiral dihydroxylation reactions. The LDH-OsW and its homogeneous analogue are found to be very efficient in performing a simultaneous asymmetric dihydroxylation (AD)-N-oxidation of a wide and varied range of aromatic, cyclic, and mono, di-, and trisubstituted olefins to obtain chiral vicinal diols with higher yields and ee's using H2O2. Further, the use of OsO4(2-)-WO4(2-) catalysts as such or in the supported form offers a simplified procedure for catalyst recycling, which shows consistent activity for a number of cycles. In this process, Os(VI) is recycled to Os(VIII) by a coupled electron transfer-mediator (ETM) system based on NMO-WO4(2-) using H2O2, leading to a mild and selective electron transfer. The one-pot biomimic synthesis of chiral diols is mediated by a recyclable trifunctional heterogeneous catalyst (LDH-PdOsW) consisting of active palladium, tungsten, and osmium species embedded in a single matrix. This protocol, which provides prochiral olefins and NMO in situ by Heck coupling and N-oxidation of NMM, respectively, required for the AD, unfolds a low cost process. We extended the present method to the one-pot synthesis of trisubstituted chiral vicinal diols with moderate to excellent ee's by AD of trisubstituted olefins that are obtained by in situ Heck arylation of disubstituted olefins. The heterogeneous trifunctional catalysts offers chiral diols with unprecedented ee's and excellent yields in the AD of prochiral cinnamates, which are obtained in situ from acrylates and halobenzenes for the first time. The new variants such as LDH support and Et3N*HX inherently composed in the heterogeneous multicomponent system and slow addition of H2O2 facilitates the hydrolysis of osmium monogylcolate ester to subdue the formation of bisglycolate ester to achieve higher ee's. Without resorting to recrystallization, the chiral diols of cinnamates thus synthesized with 99% ee's and devoid of osmium contamination are directly put to use in the synthesis of diltiazem and Taxol side chain with an overall improved yield to demonstrate the synthetic utility of the trifunctional heterogeneous catalyst. The high binding ability of the heterogeneous osmium catalyst enables the use of equimolar ratio of ligand to osmium to give excellent ee's in AD in contrast to the homogeneous osmium system in which the excess molar quantities of the expensive chiral ligand to osmium are invariably used. Further, the XRD, FT-IR, UV-vis DRS, and XPS studies indicate the retention of the coordination geometries of the specific divalent anions anchored to LDH matrix in their monomeric form during the ion exchange and after the reaction.
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Affiliation(s)
- Boyapati M Choudary
- Inorganic & Physical Chemistry Divisions, Indian Institute of Chemical Technology, Hyderabad 500 007, India.
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Barbas III CF, Ramachary DB, Chowdari NS. The First Organocatalytic Hetero-Domino Knoevenagel-Diels-Alder-Epimerization Reactions: Diastereoselective Synthesis of Highly Substituted Spiro[cyclohexane-1,2′-indan]-1′,3′,4-triones. Synlett 2003. [DOI: 10.1055/s-2003-41486] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Barbas III CF, Chowdari NS, Ramachary DB. Organocatalysis in Ionic Liquids: Highly Efficientl-Proline-Catalyzed Direct Asymmetric Mannich Reactions Involving Ketone and Aldehyde Nucleophiles. Synlett 2003. [DOI: 10.1055/s-2003-41483] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Chowdari NS, Ramachary D, Córdova A, Barbas CF. Proline-catalyzed asymmetric assembly reactions: enzyme-like assembly of carbohydrates and polyketides from three aldehyde substrates. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)02412-7] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Choudary BM, Madhi S, Chowdari NS, Kantam ML, Sreedhar B. Layered double hydroxide supported nanopalladium catalyst for Heck-, Suzuki-, Sonogashira-, and Stille-type coupling reactions of chloroarenes. J Am Chem Soc 2002; 124:14127-36. [PMID: 12440911 DOI: 10.1021/ja026975w] [Citation(s) in RCA: 647] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Layered double hydroxide and Merrifield resin supported nanopalladium(0) catalysts are prepared by an exchange of PdCl(4)(2-) followed by reduction and well characterized for the first time. The ligand-free heterogeneous layered double hydroxide supported nanopalladium (LDH-Pd(0)) catalyst using the basic LDH in place of basic ligands indeed exhibits higher activity and selectivity in the Heck olefination of electron-poor and electron-rich chloroarenes in nonaqueous ionic liquids (NAIL) over the homogeneous PdCl(2) system. Using microwave irradiation, the rate of the Heck olefination reaction is accelerated, manifold with the highest turnover frequency ever recorded in the case of both electron-poor and electron-rich chloroarenes. The basic LDH-Pd(0) shows a superior activity over a range of supported catalysts, from acidic to weakly basic Pd/C, Pd/SiO(2,) Pd/Al(2)O(3), and resin-PdCl(4)(2-) in the Heck olefination of deactivated electron-rich 4-chloroanisole. The use of LDH-Pd(0) is extended to the Suzuki-, Sonogashira-, and Stille-type coupling reactions of chloroarenes in an effort to understand the scope and utility of the reaction. The catalyst is quantitatively recovered from the reaction by a simple filtration and reused for a number of cycles with almost consistent activity in all the coupling reactions. The heterogeneity studies provide an insight into mechanistic aspects of the Heck olefination reaction and evidence that the reaction proceeds on the surface of the nanopalladium particles of the heterogeneous catalyst. TEM images of the fresh and used catalyst indeed show that the nanostructured palladium supported on LDH remains unchanged at the end of the reaction, while the XPS and evolved gas detection by TGA-MS of the used catalyst identify ArPdX species on the heterogeneous surface. Thus, the ligand-free nanopalladium supported on LDH, synthesized by the simple protocol, displays superior activity over the other heterogeneous catalysts inclusive of nanopalladium in the C-C coupling reactions of chloroarenes.
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Ramachary D, Chowdari NS, Barbas CF. Amine-catalyzed direct self Diels–Alder reactions of α,β-unsaturated ketones in water: synthesis of pro-chiral cyclohexanones. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)01500-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Choudary BM, Chowdari NS, Jyothi K, Kantam ML. Catalytic asymmetric dihydroxylation of olefins with reusable OsO(4)(2-) on ion-exchangers: the scope and reactivity using various cooxidants. J Am Chem Soc 2002; 124:5341-9. [PMID: 11996575 DOI: 10.1021/ja017889j] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Exchanger-OsO(4) catalysts are prepared by an ion-exchange technique using layered double hydroxides and quaternary ammonium salts covalently bound to resin and silica as ion-exchangers. The ion-exchangers with different characteristics and opposite ion selectivities are specially chosen to produce the best heterogeneous catalyst that can operate using the various cooxidants in the asymmetric dihydroxylation reaction. LDH-OsO(4) catalysts composed of different compositions are evaluated for the asymmetric dihydroxylation of trans-stilbene. Resin-OsO(4) and SiO(2)-OsO(4) designed to overcome the problems associated with LDH-OsO(4) indeed show consistent activity and enantioselectivity in asymmetric dihydroxylation of olefins using K(3)Fe(CN)(6) and molecular oxygen as cooxidants. Compared to the Kobayashi heterogeneous systems, resin-OsO(4) is a very efficient catalyst for the dihydroxylation of a wide variety of aromatic, aliphatic, acyclic, cyclic, mono-, di-, and trisubstituted olefins to afford chiral vicinal diols with high yields and enantioselectivities irrespective of the cooxidant used. Resin-OsO(4) is recovered quantitatively by a simple filtration and reused for a number of cycles with consistent activity. The high binding ability of the heterogeneous osmium catalyst enables the use of an equimolar ratio of ligand to osmium to give excellent enantioselectives in asymmetric dihydroxylation in contrast to the homogeneous osmium system in which excess molar quantities of the expensive chiral ligand to osmium are invariably used. The complexation of the chiral ligand (DHQD)(2)PHAL, having very large dimension, a prerequisite to obtain higher ee, is possible only with the OsO(4)(2-) located on the surface of the supports.
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Affiliation(s)
- Boyapati M Choudary
- Contribution from the Indian Institute of Chemical Technology, Hyderabad 500 007, India
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Choudary BM, Chowdari NS, Jyothi K, Kumar NS, Kantam ML. A new bifunctional catalyst for tandem Heck-asymmetric dihydroxylation of olefins. Chem Commun (Camb) 2002:586-7. [PMID: 12120135 DOI: 10.1039/b110681n] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new bifunctional catalyst consisting of active palladium and osmium species anchored on silica gel through a mercaptopropyl spacer and a cinchona alkaloid respectively has been prepared for the first time and used in the heterogeneous tandem Heck-asymmetric dihydroxylation of olefins to afford diols with excellent yields and enantiomeric excesses (ee's) in presence of N-methylmorpholine N-oxide or K3Fe(CN)6 as cooxidants.
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Choudary BM, Chowdari NS, Madhi S, Kantam ML. A Trifunctional Catalyst for the Synthesis of Chiral Diols N.S.C. and S.M. thank the Council of Scientific and Industrial Research, India, for providing research fellowships. We also thank Prof. I. E. Marko for his helpful comments. Angew Chem Int Ed Engl 2001; 40:4619-4623. [PMID: 12404366 DOI: 10.1002/1521-3773(20011217)40:24<4619::aid-anie4619>3.0.co;2-u] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Choudary BM, Chowdari NS, Kantam ML, Raghavan KV. Catalytic asymmetric dihydroxylation of olefins with new catalysts: the first example of heterogenization of OsO(4)(2-) by ion-exchange technique. J Am Chem Soc 2001; 123:9220-1. [PMID: 11552854 DOI: 10.1021/ja016101u] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- B M Choudary
- Indian Institute of Chemical Technology, Hyderabad 500 007, India
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Choudary BM, Chowdari NS, Kantam ML. Montmorillonite Clay Catalyzed Tosylation of Alcohols and Selective Monotosylation of Diols with p-Toluenesulfonic Acid: An Enviro-Economic Route. Tetrahedron 2000. [DOI: 10.1016/s0040-4020(00)00626-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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