Late-stage intermolecular CH activation for lead diversification: a highly chemoselective oxyfunctionalization of the C-9 position of potent bryostatin analogues.

Paul A Wender; Michael K Hilinski; Alexander V W Mayweg

doi:10.1021/ol047859w

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Late-stage intermolecular CH activation for lead diversification: a highly chemoselective oxyfunctionalization of the C-9 position of potent bryostatin analogues.

Paul A Wender·Michael K Hilinski·Alexander V W Mayweg

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Abstract

Treatment of highly potent and densely functionalized bryostatin analogue 1 with dimethyldioxirane afforded the C-9 hydroxylated hemiketal 2 via oxyfunctionalization of the C9-CH bond, one of 12 CH bonds geminal to an oxygen substituent in 1. When bryostatin analogue 3 was subjected to identical conditions, oxidation of a C-26 secondary hydroxyl group was found to compete with C-9 hydroxylation. Complete selectivity for C-9 hydroxylation was restored upon acylation of the C-26 secondary alcohol.

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Bryostatins Hydrogen Bonding Hydroxylation Macrolides Magnetic Resonance Spectroscopy Protein Kinase C Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, P.H.S.

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Paul A Wender, Michael K Hilinski, Alexander V W Mayweg. 2005-01-06. Late-stage intermolecular CH activation for lead diversification: a highly chemoselective oxyfunctionalization of the C-9 position of potent bryostatin analogues.. https://doi.org/10.1021/ol047859w

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