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Gangathade N. Total Synthesis of Macrocyclolipopeptide Dysoxylactam A. J Org Chem 2024; 89:3954-3961. [PMID: 38426216 DOI: 10.1021/acs.joc.3c02780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
A highly stereoselective total synthesis of potent multidrug-resistant reverser dysoxylactum A has been accomplished in the longest linear sequences of 20 steps with an overall 10.2% yield. The key steps of this synthesis included Brown's crotylation, Evans alkylation, the Carreira protocol to generate the stereogenic center, and Yamaguchi macrolactonization.
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Affiliation(s)
- Namdeo Gangathade
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
- Academy of Scientific and Innovation Research (AcSIR), Ghaziabad 201002, India
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2
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Ahmed S, Nur-E-Alam M, Parveen I, Threadgill MD, Orton JB, Hafizur RM, Khan I, Al-Oqail M, Al-Rehaily AJ. Compounds Related to Saudin and Three New Series of Diterpenoids from Clutia lanceolata. JOURNAL OF NATURAL PRODUCTS 2023; 86:1129-1149. [PMID: 37128771 DOI: 10.1021/acs.jnatprod.2c00761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Clutia lanceolata is a medicinal plant native to Ethiopia and sub-Saharan Africa and to the Arabian Peninsula. It is used traditionally in Saudi Arabia for the treatment of diabetes. Previous phytochemical analysis of this species has been limited to the identification of methylthiocoumarins. Further work has led to isolation of 19 new diterpenoids in three structural classes. Their structures were established by HRMS and by a range of NMR techniques (1H, 13C, COSY, NOESY, HSQC, HMBC), with confirmation for some examples by X-ray crystallography. NOESY and 1H-1H NMR coupling constants gave the relative stereochemical configurations and conformational information, with absolute configurations being established through X-ray crystallography. One example closely related to the known hypoglycemic compound saudin (found in C. richardiana and also in C. lanceolata) and one with a different core tetracycle were found to enhance strongly the glucose-triggered release of insulin from murine pancreatic islets. Biosynthetic proposals for the three groups of new diterpenoids by alternative cyclization of a common precursor are put forward. Lanceolide P (16) is proposed as a lead compound for further development for the treatment of diabetes.
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Affiliation(s)
- Sarfaraz Ahmed
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
| | - Mohammad Nur-E-Alam
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
| | - Ifat Parveen
- Department of Life Sciences, Aberystwyth University, Aberystwyth SY23 3DA, United Kingdom
| | - Michael D Threadgill
- Department of Life Sciences, Aberystwyth University, Aberystwyth SY23 3DA, United Kingdom
- Department of Life Sciences, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - James B Orton
- UK National Crystallography Service, School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Rahman M Hafizur
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan
| | - Israr Khan
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi 75270, Pakistan
| | - Mai Al-Oqail
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
| | - Adnan J Al-Rehaily
- Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
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3
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Acosta JAM, Muddala R, Barbosa LCA, Boukouvalas J. Total Synthesis of the Antitumor Antibiotic Basidalin. J Org Chem 2016; 81:6883-6. [DOI: 10.1021/acs.joc.6b01255] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jaime A. M. Acosta
- Department
of Chemistry, Pavillon Alexandre-Vachon, Université Laval, 1045 Avenue de la Médecine, Quebec
City, Quebec G1V 0A6, Canada
| | - Ramesh Muddala
- Department
of Chemistry, Pavillon Alexandre-Vachon, Université Laval, 1045 Avenue de la Médecine, Quebec
City, Quebec G1V 0A6, Canada
| | - Luiz C. A. Barbosa
- Department
of Chemistry, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais (UFMG), Av. Pres. Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, 31270-901, MG, Brazil
| | - John Boukouvalas
- Department
of Chemistry, Pavillon Alexandre-Vachon, Université Laval, 1045 Avenue de la Médecine, Quebec
City, Quebec G1V 0A6, Canada
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4
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Raghavan S, Rajendar S. Stereoselective total synthesis of (−)-nupharamine utilizing an α-chlorosulfide and a sulfinimine for C–C bond formation. Org Biomol Chem 2016; 14:131-7. [DOI: 10.1039/c5ob01750e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A stereoselective route to nupharamine is disclosed using α-chlorosulfide and sulfinimine as reactive intermediates.
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Affiliation(s)
- Sadagopan Raghavan
- Division of Natural Product Chemistry
- Indian Institute of Chemical Technology
- Hyderabad 500007
- India
| | - Sheelamanthula Rajendar
- Division of Natural Product Chemistry
- Indian Institute of Chemical Technology
- Hyderabad 500007
- India
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5
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Jacob S, Brooks JL, Frontier AJ. No acid required: 4π and 6π electrocyclization reactions of dienyl diketones for the synthesis of cyclopentenones and 2H-Pyrans. J Org Chem 2014; 79:10296-302. [PMID: 25325706 PMCID: PMC4227568 DOI: 10.1021/jo501914w] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Indexed: 12/19/2022]
Abstract
The 1,6-conjugate addition of nucleophiles to dienyl diketones produces either cyclopentenone or 2H-pyran products with high selectivity through either Nazarov (4π) or 6π electrocyclization, respectively. The outcome of the reaction is dependent upon the nature of the nucleophile used. Nucleophiles that are anionic or easily deprotonated exclusively produce cyclopentenones via Nazarov cyclization, whereas the neutral nucleophile DABCO promotes 6π cyclization to afford 2H-pyrans. Experimental evidence is presented for both retro-4π and -6π electrocyclization in these systems, lending support to the bifurcated mechanistic hypothesis proposed for these cyclizations.
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Affiliation(s)
- Steven
D. Jacob
- Department of Chemistry, University of
Rochester, Rochester, New York 14627, United
States
| | - Joshua L. Brooks
- Department of Chemistry, University of
Rochester, Rochester, New York 14627, United
States
| | - Alison J. Frontier
- Department of Chemistry, University of
Rochester, Rochester, New York 14627, United
States
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Nakamura A, Kageyama T, Goto H, Carrow BP, Ito S, Nozaki K. P-Chiral Phosphine–Sulfonate/Palladium-Catalyzed Asymmetric Copolymerization of Vinyl Acetate with Carbon Monoxide. J Am Chem Soc 2012; 134:12366-9. [DOI: 10.1021/ja3044344] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Akifumi Nakamura
- Department of Chemistry and Biotechnology,
Graduate
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeharu Kageyama
- Department of Chemistry and Biotechnology,
Graduate
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroki Goto
- Department of Chemistry and Biotechnology,
Graduate
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Brad P. Carrow
- Department of Chemistry and Biotechnology,
Graduate
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Shingo Ito
- Department of Chemistry and Biotechnology,
Graduate
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kyoko Nozaki
- Department of Chemistry and Biotechnology,
Graduate
School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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