Synthetic studies of carzinophilin. Part 2: Synthesis of 3,4-dibenzyloxy-2-methylidene-1-azabicyclo[3.1.0]hexane systems corresponding to the C1–C17 fragment of carzinophilin

A model compound bearing the C1–C17 fragment of carzinophilin was synthesized. The synthesis involved coupling reaction of a cyclic thioimidate with the 4H-oxazol-5-one derivative, ring-opening of the 4H-oxazol-5-one to furnish a dehydropeptide system, elaboration of the C1–C6 enolamide, and construction of the aziridine ring as key steps.