Derivatives of A54145 cyclic peptides

Abstract

A new group of cyclic peptide derivatives, the A54145 cyclic peptide derivatives, which have the general formula: ##STR1## wherein: R is C.sub.8 -C.sub.18 -alkyl, optionally substituted C.sub.8 -C.sub.18 -alkanoyl or C.sub.8 -C.sub.18 -alkenoyl; (R,R.sup.2)-Trp represents a group of formula ##STR2## (Lys-R.sup.1) represents --NH(CH.sub.2).sub.4 CH(NHR.sup.1)CO--; R.sup.1 is hydrogen or an amino-protecting group; and R.sup.2 is hydrogen; or R and R.sup.2, taken together, represent a C.sub.8 -C.sub.18 -alkylidene group; X is Ile or Val; and Y is Glu or 3-MG; provided that: 1) when R.sup.1 =H, X=Ile and Y=Glu or 3-MG, R cannot be 8-methylnonanoyl, 8-methyldecanoyl or n-decanoyl; 2) when R.sup.1 =H, X=Val and Y=3-MG, R cannot be 8-methyldecanoyl; and 3) when R.sup.1 =H, X=Val and Y=Glu, R cannot be 8-methylnonanoyl; and 4) when R.sup.1 is an amino protecting group, R cannot be 8-methylnonanoyl, 8-methyldecanoyl, or n-decanoyl; and their salts are antibacterial agents or intermediates to such agents. Formula 1 compounds wherein R.sup.2 is hydrogen improve growth perforamnce in animals; thus, feed compositions for promoting growth in animals such as poultry and methods for increasing growth in animals using these compositions, are also provided.

Dependencies are inferred from the claim text.