A MODIFICATION OF THE N-TERMINAL AMINO-ACID IN THE EREMOMYCIN AGLYCONE

An Edman degradation of the antibiotic eremomycin aglycone produced th e corresponding hexapeptide, which was aminoacylated with D-lysine, D- histidine or D-tryptophan derivatives to give new heptapeptide analogs of the eremomycin aglycone. The aminoacylation of the eremomycin agly cone produced an octapeptide analog. The substitution of D-lysine for the N-terminal N-methyl-D-leucine does not seriously affect the in vit ro antibacterial properties of the eremomycin aglycone whereas the hep tapeptides with the N-terminal D-tryptophan or D-histidine moieties an d the octapeptide with the N-terminal D-lysine are practically devoid of the antibacterial properties.