Regioselective preparation of 2-substituted 3,4-diaryl pyrroles: a concise total synthesis of ningalin B.

J Org Chem

Discovery Research, Johnson & Johnson Pharmaceutical Research and Development, L.L.C., 1000 Route 202, Raritan, New Jersey 08869, USA.

Published: December 2002

Methylisocyanoacetate undergoes a 2 + 3 cycloaddition with alpha,beta-unsaturated nitriles to provide a regioselective synthesis of 2-substituted 3,4-diaryl pyrroles. The ease of preparation of alpha,beta-unsaturated nitriles allows the rapid synthesis of pyrroles with varied substituents. Using this method, a key intermediate (1) for the synthesis of the marine natural products lukianol A, lamellarin O, and lamellarin Q was prepared in two steps. A total synthesis of ningalin B (11) was also accomplished utilizing this methodology.

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http://dx.doi.org/10.1021/jo026445iDOI Listing

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