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The total synthesis of (-)- cyanthiwigin F by means of double catalytic enantioselective alkylation. J.A. Enquist, Jr., B.M. Stoltz , Nature 2008,453,1228 Presented by Vijayarajan Devannah on 5/7/2013. About Professor Brain M. Stoltz. Education and Professional Experience - PowerPoint PPT Presentation
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The total synthesis of (-)-cyanthiwigin F by means of double catalytic enantioselective alkylation
J.A. Enquist, Jr., B.M. Stoltz, Nature 2008,453,1228
Presented by Vijayarajan Devannah on 5/7/2013
About Professor Brain M. Stoltz
Education and Professional Experience•B.S., Indiana University of Pennsylvania 1993•Ph.D., Yale University (John Wood) 1997•NIH posdoctoral Fellow, Harvard University ( E. J. Corey ) 1998-2000•Currently professor of chemistry at California Institute of Technology, Pasadena.Honors and Awards•Camille and Henry Dreyfus New Faculty Award, 2000•Glaxosmithkline Chemistry scholar Award 2002 and 2003•Amgen Young investigator Award 2003•Arthur C Cope Scholar Award from the American Chemical Society 2005•E J Corey Award for outstanding original contribution in the organic synthesis by a young investigator, 2009•H.C. Brown Lecturer in Organic Chemistry, Purdue University, Indiana, 2011
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About Cyanthiwigin F• Isolated from the sea sponge Myrmekioderma styx,• Cyanthiwigin F is one of 30 known cyanthiwigin natural products,
which belongs to a larger class of bioactive molecules known as cyathins.
• Cyathins display a wide range of biological properties including antimicrobial activity, antineoplastic actions, stimulation of nerve growth factor synthesis, and κ-opioid receptor agonism.
• Cyanthiwigin F exhibits cytotoxicity activity against human primary tumour cells with a half-maximal inhibitory concentration of 3.1μg/ml.
Synthetic Challenges posed by Cyanthiwigin F• Construction of two all-carbon quaternary stereocentres at the A-B
and B-C ring juncture.• Fused 5-6-7 ring system.
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Retrosynthesis
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Synthesis of diketone through stereoablative and enantioselective double
allylation
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Stereochemical analysis of bis(β-ketoester)
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Synthesis of bicyclic aldehyde through olefin metathesis
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Final Stages and completion of total synthesis of cyanthiwigin F
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Conclusion• They achieved the catalytic enantioselective synthesis of the
cyanthin diterpenoid (-)-cyanthiwigin F in 10 steps.• Total yield is 1.8%• Introduction of two chiral centers in one pot with excellent ee• Tandem ring-closing and cross metathesis• No protection and Deprotection involved.
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Thank You
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