The Structures of Sulfomycins II and III.

Abstract

The isolation and biological activities of sulfur-containing antibiotics sulfomycins I, II and III from the fermentation broth of Streptomyces viridochromogenes MCRL-0368 were reported by Egawa et ai in 1969.1} The structure of sulfomycin I was determined on the basis of chemical degradations and NMRtechniques2'3) to be a cyclic thiopeptide antibiotic represented by thiostrepton4), berninamycin3) and thiopeptin5). The structures of sulfomycins II and III, however, remained unclear. Recently, Seto and his colleagues reported a 1063 series of new thiopeptide antibiotics, promothiocins A