ABSTRACT
The stambomycins are a family of bioactive macrolides isolated from Streptomyces ambofaciens. Aside from two stereocenters installed through cytochrome P450 oxidations, their stereochemistry has been predicted by sequence analysis of the polyketide synthase. We report a synthesis of the C1-C27 fragment of stambomycin D, the spectroscopic data of which correlates well with that of the natural product, further validating predictive sequence analysis as a powerful tool for stereochemical assignment of complex polyketide natural products.
Subject(s)
Anti-Bacterial Agents/pharmacology , Cytochrome P-450 Enzyme System/metabolism , Macrolides/chemistry , Polyketide Synthases/metabolism , Polyketides/chemistry , Anti-Bacterial Agents/chemistry , Biological Products , Cytochrome P-450 Enzyme System/chemistry , Macrolides/chemical synthesis , Molecular Structure , Polyketide Synthases/chemistry , Streptomyces/chemistryABSTRACT
A Yamaguchi-type cyclization of 5 and subsequent photochemical oxidation of the furanic ring are the key steps in the first synthesis of the marine metabolite (+)-luffalactone 4 and its epimer at C-16, 16-epi-luffalactone, 27. With this work, we have successfully established the absolute configuration of the natural product. The key intermediate 5 was obtained from the easily accessible diacetate 6a/6b.