Abstract: 4-Dedimethylaminotetracyclines and the corresponding 5a,6-anhydro derivatives having an oxo, hydroxy, substituted imino, amino or substituted amino group other than dimethylamino at the C.multidot.4-position useful as antimicrobial agents. The 4-oxo-4-dedimethylaminotetracyclines are prepared by oxidation of tetracyclines with a hydrocarbon dicarboxylic acid haloimide and then converted by reduction to the corresponding 4-hydroxy compounds or by reaction with a primary amine to 4-substituted imino derivatives. The latter compounds are reduced to 4-amino derivatives which are reductively methylated or alkylated to 4-substituted-4-dedimethylaminotetracyclines. Dehydration of the tetracycline compounds affords the corresponding 5a,6-anhydro compounds.

Abstract: 4-Dedimethylaminotetracyclines and the corresponding 5a,6-anhydro derivatives having an oxo, hydroxy, substituted imino, amino or substituted amino group other than dimethylamino at the C.multidot.4-position useful as antimicrobial agents. The 4-oxo-4-dedimethylaminotetracyclines are prepared by oxidation of tetracyclines with a hydrocarbon dicarboxylic acid haloimide and then converted by reduction to the corresponding 4-hydroxy compounds or by reaction with a primary amine to 4-substituted imino derivatives. The latter compounds are reduced to 4-amino derivatives which are reductively methylated or alkylated to 4-substituted-4-dedimethylaminotetracyclines. Dehydration of the tetracycline compounds affords the corresponding 5a,6-anhydro compounds.