Synthesis of melithiazol B and related compounds via oxidative degradationof myxothiazol A and Z

The synthesis of melithiazol B (4) has been accomplished in five steps and 19% overall yield starting from myxothiazol A (1). Key steps include the co nversion of the amide into the methyl ester 4, oxygenation to hydroperoxide s 7 and 9, and subsequent Hock cleavage to ketones 11 and 12, followed by a Wittig reaction to give 4 and 13. The biological activities of intermediat es, melithiazol B and derivatives thereof are compared.