Alkylated derivatives of antibiotic BM123.gamma.

A compound selected from the group consisting of those of the formula:

• ##STR8## wherein R is a moiety selected from the group consisting of those of the formulae:
• ##STR9## R.sub.2 is selected from the group conisting of lower alkyl, halo substituted lower alkyl and phenyl lower alkyl;
• R.sub.3 is selected from the group consisting of lower alkyl, halo substituted lower alkyl, lower alkenyl, lower cycloalkyl, phenyl, acetamidophenyl, nitrophenyl, mercaptophenyl, anisyl, tolyl, phenyl lower alkyl, acetamidophenyl lower alkyl, nitrophenyl lower alkyl, mercaptophenyl lower alkyl, anisyl lower alkyl and tolyl lower alkyl;
• and R.sub.2 and R.sub.3 taken together with the associated methylidyne group is cyclopentyl, mono-lower alkyl substituted cyclopentyl, di-lower alkyl substituted cyclopentyl, tri-lower alkyl substituted cyclopentyl, cyclohexyl, mono-lower alkyl substituted cyclohexyl, di-lower alkyl substituted cyclohexyl or tri-lower alkyl substituted cyclohexyl;
• and the pharmacologically acceptable acid-addition salts thereof.