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Synthesis of an Advanced C10–C32 Spiroacetal Fragment and Assignment of the Absolute Configuration of Spirangien A

✍ Scribed by Ian Paterson; Alison D. Findlay; Edward A. Anderson

Publisher
John Wiley and Sons
Year
2007
Tongue
English
Weight
134 KB
Volume
46
Category
Article
ISSN
0044-8249

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✦ Synopsis

Spirangiens A (1, Scheme 1) and B (2), [1] isolated by the research group of Höfle from the epothilone-producing myxobacterium Sorangium cellulosum (strain So ce90), are polyketide metabolites [2] that possess potent antifungal and cytotoxic activity (IC 50 0.7 ng mL À1 against L929 mouse fibroblast cell line). From a structural perspective, the spirangiens contain 14 stereocenters, and include a densely functionalized spiroacetal core appended with a delicate pentaene side chain that bears a terminal carboxy group. Spirangiens A and B differ only with the presence of a methyl or ethyl substituent at C31.

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