Eremomycin--new glycopeptide antibiotic: chemical properties and structure.

By a combination of chemical and spectroscopic (1H and 13C NMR) studies the structure of a glycopeptide antibiotic eremomycin has been elucidated. It is closely related to vancomycin, but differs in sugar and chlorine content. The eremomycin aglycone contains monodechlorovancomycinic acid; the only chlorine atom is situated in the second amino acid after the N-terminal amino acid residue of the peptide. The sugar part is composed of glucose and two residues of an amino sugar shown to be 2,3,6-trideoxy-3-amino-C-3-methyl-L-arabino-hexopyranose (4-epi-vancosamine). One of the amino sugar residues is a component of the disaccharide 2-O-(alpha-L-4-epi-vancosaminyl)-beta-D-glucopyranose, attached to a triphenyl ether moiety; the position of another one is at the serine oxygen in the C-terminal region of the aglycone.