Biosynthesis of Berninamycin: Incorporation of ~(13)C-Labeled Amino Acids

摘要

Two-dimensional NMR and FABMS/MS studies agree with the structure for berninamycin A proposed by Abe et al. (Tetrahedron Lett. 1988, 29,1401 — 1404). Biosynthetic studies with ~(13)C-enriched amino acids confirm our earlier results that the dehydroalanine units are formed by dehydration of serine. The oxazoles are formed by condensing a threonine unit with a serine or another threonine with dehydration, and the thiazole is formed by combining a cysteine with a serine with dehydration. The biosynthesis of the pyridine ring is similar to piperidine/hydroxypyridine ring formation in thiostrepton and nosiheptide. The biogenesis of berninamycin A is also discussed.