A-21978C cyclic peptides

Abstract

A-21978C cyclic peptides of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, an amino-protecting group , 8-methyldecanoyl, 10-methylundecanoyl, 10-methyldodecanoyl, the specific C.sub.10 -alkanoyl group of A-21978C factor C.sub.0 and the specific C.sub.12 -alkanoyl groups of A-21978C factors C.sub.4 and C.sub.5 ; R.sup.1 and R.sup.2 are, independently, hydrogen or an amino-protecting group, and salts thereof, are prepared by enzymatic deacylation of an antibiotic selected from A-21978C complex, A-21978C factors C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4 and C.sub.5 and blocked A-21978C complex and factors C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4 and C.sub.5, using an enzyme produced by the Actinoplanaceae, preferably by Actinoplanes utahensis. The A-21978C cyclic peptides and salts thereof are useful intermediates to prepare new semi-synthetic antibacterial agents.

Dependencies are inferred from the claim text.