2-Carboxamido-substituted tetracyclines and process for their manufacture

DETAILED DESCRIPTION We claim: 1.
A 2-carboxamido-substituted tetracycline of the general formula I ##SPC5## in which R.
sub.
1 is lower, optionally branched alkyl, R.
sub.
2 and R.
sub.
3 may be identical or different and each is hydrogen, optionally branched alkyl of 1 to 6 carbon atoms which may carry one or more identical or different substituents selected from the group consisting of hydroxy, lower dialkylamino, lower dialkylcarbamoyl, lower alkoxycarbonyl, phenyl, a heterocyclic group, especially a 5- or 6-membered ring which may include oxygen and/or nitrogen, and carboxyl, in this latter case the alkyl moiety may also carry amino; or cycloalkyl of 5 to 7 carbon atoms, and in which R.
sub.
2 and R.
sub.
3 may also be closed to form a saturated or unsaturated 5- or 6-membered ring which may include nitrogen or oxygen and may carry one or more substituents selected from the group consisting of lower alkyl, lower hydroxyalkyl, lower carboxyalkyl, hydroxyl or carboxyl, R.
sub.
4 and R.
sub.
5 may be identical or different and each is hydrogen or hydroxy, R.
sub.
6 is hydrogen or methyl, R.
sub.
5 and R.
sub.
6 together are methylene, and R.
sub.
7 is hydrogen, chlorine, bromine, dimethylamino or diethylamino.
2.
A compound of claim 1 which is N-(1-ethoxycarbonyl-1-dimethylamino-methyl)-tetracycline.
3.
A compound of claim 1 which is N-(1-n-butoxycarbonyl-1-dimethylamino-methyl)-tetracycline.
4.
A compound of claim 1 which is N-(1-ethoxycarbonyl-1-pyrrolidyl(1)-methyl)-tetracycline.
5.
A compound of claim 1 which is N-(1-n-butoxycarbonyl-1-pyrrolidyl(1)-methyl)-tetracycline.
6.
A compound of claim 1 which is N-(1-ethoxycarbonyl-1-piperidyl(1)-methyl)-tetracycline.
7.
A compound of claim 1 which is N-(1-n-butoxycarbonyl-1-piperidyl(1)-methyl)-tetracycline.
8.
A compound of claim 1 which is N-(1-ethoxycarbonyl-1-morpholinyl(4)-methyl)-tetracycline.
9.
A compound of claim 1 which is N-[1-ethoxycarbonyl-1-(4-.
beta.
-hydroxyethylpiperazyl(1))-methyl]-tetracyc line.
10.
A compound of claim 1 which is N-(1-ethoxycarbonyl-1-dimethylamino-methyl)-oxytetracycline