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Total syntheses of isodomoic acids G and H: an exercise in tetrasubstituted alkene synthesis.

ABSTRACT: A unified approach to the pyrrolidine triacid natural products isodomoic acids G and H has been developed. Total syntheses of both natural products were completed, and determination of the correct stereostructure of isodomoic acid G was established by comparing 5'-(R) and 5'-(S) isomers to a sample of authentic material. A nickel-catalyzed cyclization constructs the pyrrolidine ring while simultaneously establishing either the E or Z stereochemistry of an exocyclic tetrasubstituted alkene. Stereoselective assembly of both the E- and Z-alkenes of the natural products is made possible by a predictable strategy that alters the timing of substituent introduction to control alkene stereochemistry.

SUBMITTER: Ni Y

PROVIDER: S-EPMC2788205 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Total syntheses of isodomoic acids G and H: an exercise in tetrasubstituted alkene synthesis.

Ni Yike Y Kassab Refaie M RM Chevliakov Maxim V MV Montgomery John J

Journal of the American Chemical Society 20091201 48

A unified approach to the pyrrolidine triacid natural products isodomoic acids G and H has been developed. Total syntheses of both natural products were completed, and determination of the correct stereostructure of isodomoic acid G was established by comparing 5'-(R) and 5'-(S) isomers to a sample of authentic material. A nickel-catalyzed cyclization constructs the pyrrolidine ring while simultaneously establishing either the E or Z stereochemistry of an exocyclic tetrasubstituted alkene. Stere ...[more]

PMID: 19899794

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