A concise and fully selective synthesis of the ant venom alkaloid (3S,5R,8S,9S)-3-butyl-5-propyl-8-hydroxyindolizidine

Abstract

A seven-step synthesis of (3S,5R,8S,9S)-3-butyl-5-propyl-8-hydroxyindolizidine (2), an ant venom alkaloid isolated from Myrmicaria melanogaster, is disclosed with an overall yield of 28.9%. The key feature of the synthesis is the use of the iodocyclization for the introduction of the hydroxyl group of the 3-piperidinol. Remarkably, all the reaction steps proceeded with excellent chemo-, regio- and/or diastereoselectivities.