Synthesis of lepiochlorin, an antibiotic metabolite of a fungus cultivated by ants

The fungal metabolite lepiochlorin has been synthesized from allylmethoxyethoxymethyl ether and the dianion of 2-phenylthiopropionic acid. The resulting lactone was converted to the butenolide and halogen functions introduced by hydrolysis of the MEM group and treatment with thionyl chloride followed by N-bromosuccinimide. Reaction with silver acetate yielded lepiochlorin.