Process for producing 3-o-demethylaminoglycoside and novel

Abstract

An improved process for producing 3-O-demethylfortimicins and other O-methyl-containing aminoglycoside antibiotics comprising the steps of reacting the fortimicin to be 3-O-demethylated with a borontrihalide and recovering the 3-O-demethylfortimicin from the reaction mixture. 3-O-Demethylfortimicin derivatives which can be prepared by this process include compounds represented by the formula: ##STR1## wherein: R.sub.1 and R.sub.2 are hydrogen or methyl with the limitation that one of either R.sub.1 or R.sub.2 must be hydrogen; R.sub.3 is hydrogen or methyl; R.sub.4 and R.sub.11 are the same or different members of the group consisting of hydrogen, acyl, aminoacyl, diaminoacyl, N-loweralkylaminoacyl, N,N-diloweralkylaminoacyl, hydroxy-substituted aminoacyl, loweralkyl, aminoloweralkyl, diaminoloweralkyl, hydroxyloweralkyl, N-loweralkylaminoloweralkyl, N,N-diloweralkylaminoloweralkyl, N-loweralkylaminohydroxyloweralkyl and N,N-diloweralkylaminohydroxyloweralkyl; R.sub.5 and R.sub.6 are hydrogen or amino with the limitation that one of either R.sub.5 and R.sub.6 must be hydrogen; R.sub.7 and R.sub.8 are selected from the group consisting of either hydrogen, hydroxy, amino and chloro with the limitation that one of either R.sub.7 or R.sub.8 must be hydrogen; R.sub.9 and R.sub.10 are hydrogen or hydroxy with the limitation that one of either R.sub.9 or R.sub.10 must be hydrogen; and the pharmaceutically acceptable salts thereof. Compounds other than those wherein R.sub.1 is hydrogen, R.sub.2 is methyl, R.sub.3 is hydrogen, R.sub.5 is amino, R.sub.8 is hydroxy and R.sub.10 is hydroxy when R.sub.4' -R.sub.5' is saturated, are novel and are useful as antibiotics, antibacterial agents, and as intermediates for producing other useful fortimicin derivatives.