Total synthesis of haploscleridamine, villagorgin A and an approach towards lissoclin C.

An investigation of asymmetric total syntheses of three indole-imidazole alkaloids from histidine are described. A common advanced piperidinone was contructed a ring-closing metathesis which was then subjected to a modified Fischer indole synthesis. Deprotection of an -tosyl group a dissolving metal reduction affords haploscleridamine which upon reaction with aqueous formaldehyde in trifluoroethanol provided villagorgin A.