Synthesis of Homocarbonyltopsentine Derivatives

Abstract

Homocarbonyltopsentines I are known to exhibit interesting anti-inflammatory activity in vivo. In order to study the role of the heterocycles in the modulation of their activity, several analogues in which indoles were replaced either by substituted indoles or by bioisosteric heterocycles such as pyrrolo[2,3-b]pyridine, benzo[b]thiophene and pyridine were synthesised. The synthesis is based on selective halogen-metal exchange on triiodoimidazole 1 and subsequent addition to formylated heterocycles.

Key words

indoles - metalation - regioselectivity - addition reactions - palladium

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