Synthesis of 9-epi-Mitomycin B: The First Inversion of the C-9 Stereochemistry in Mitomycin B

Article abstract of DOI:10.1021/jo00286a021

9-epi-Mitomycin B (2b) with the same C-9 stereochemistry as mitomycin C(1) was synthesized from mitomycin B (2a) through inversion at the C-9 position. 10-O-Decarbamoylmitomycin D (8a), derived from 2a in two steps, was employed as the substrate for the epimerization.The 10-hydroxymethyl group in 8a was epimerized on treatment with diazabicyclo<5.4.0>undec-7-ene to afford 8b.Successive transformation performed on the functional groups of 8b gave the desired 2b in four steps.The stereochemistry in 2b was confirmed by conversion of 2b to the known mitomycin F (4).