An NMR study of eremomycin and its derivatives.

Abstract

Complete 1H and 13C NMR assignments are presented for eremomycin (1) and some of its desglycosylated derivatives 2, 3 and compared to the structurally closely related glycopeptide vancomycin. Primary structure and stereochemistry of eremomycin is corroborated by the present high field total correlation spectroscopy, NOESY and heteronuclear multiple-bond correlation NMR methods. A rough motional characterization of the title compound is attempted by 13C-T1 and 13C-[1H] NOE measurements. Dimerization of eremomycin is observed both in DMSO-d6-CCl4 and D2O solutions. Complexation with cell wall analogue dipeptide Ac-D-Ala-D-Ala is also demonstrated.