Efficient assembly of the phomactin core via two different macrocyclization protocols.

T J Houghton; S Choi; V H Rawal

doi:10.1021/ol0163833

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PubMed · 11700095

Efficient assembly of the phomactin core via two different macrocyclization protocols.

T J Houghton·S Choi·V H Rawal

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Abstract

[reaction--see text] The core structure of phomactins C and D was assembled by an efficient strategy starting from 3,4-dimethylcyclohexen-2-one. Key reactions include (1) a high yielding and highly diastereoselective Michael addition of a mixed cuprate, (2) a carbonylative alkyne-enoltriflate coupling or an intramolecular addition of an acetylide onto an aldehyde to form the macrocycle, (3) chemoselective Michael addition of a cuprate to an enynone, to give the carbon framework of desformyl phomactin C or D, and finally (4) regioselective addition of a thia-nucleophile to the more reactive beta-position of the resulting dienone.

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Crystallography, X-Ray Cyclization Epoxy Compounds Heterocyclic Compounds, 3-Ring Indicators and Reagents Platelet Activating Factor Journal Article Research Support, Non-U.S. Gov't

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T J Houghton, S Choi, V H Rawal. 2001-11-15. Efficient assembly of the phomactin core via two different macrocyclization protocols.. https://doi.org/10.1021/ol0163833

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