Cremeomycin, a novel cytotoxic antibiotic from Streptomyces cremeus. Structure elucidation and biological activity.

completely novel structure in this class of compounds. Fermentation and Isolation Cremeomycinwas originally reported by Bergy and Pyke at the Upjohn Company in 1967 from Streptomyces cremeus NRRL3241.11} Neither a structural formula nor functional group information was reported. Physico-chemical and Biological Properties Cremeomycinis a bright yellow solid that is soluble in solvents from dichloromethane to water but insoluble in hexane. Solutions of the compound slowly decompose when exposed to light at room temperature, but fairly concentrated solutions are stable for weeksat 0°Cwhen protected from light. Cremeomycinwas shown in the present study to inhibit the growth of murine lymphocytic leukemia L-1210 cells, with IC50 l.-5/zg/ml, and