Synthesis of Natural Fimbrolides

Abstract

Starting from citraconic anhydride, a three-step approach to fimbrolide congener is reported by taking the advantage of a regioselective Grignard reaction with an anhydride, followed by a dehydrative cyclization and double bromination-dehydrobromination sequence. Starting from N-(4-tolyl)maleimide, an eight-step synthesis of two natural fimbrolides is reported with good yields via the synthesis of requisite butylmaleic anhydride, its regioselective Grignard coupling reaction, and a bromination-dehydrobromination pathway.

Key words

butylmaleic anhydride - regioselective Grignard coupling - butenolides - bromination - fimbrolides

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