The Structures of Cirratiomycin A and B, the New Peptide Antibiotics

Abstract
The structures of cirratiomycin A and B have been elucidated by a degradative study and 1H-and 13C-NMR spectral analysis. It is revealed here that cirratiomycin A and B are heptapeptides containing three unusual new amino acids, viz, hydroxymethylserine, 2,3,4,5-tetrahydropyridazine-3-carboxylic acid and 2,3-didehydroisoleucine.