The present invention relates to new antimicrobial compounds, their synthesis and their use for treatment of mammalian infections The present invention aims at the generation of new compounds with activity against mycobacteria as potential new tuberculosis drugs to overcome problems concerning resistance and drug intolerance. This aim has been solved by providing compounds of the formula I wherein R 1 and R 2 are, independently of each other, NO 2 , NR 7 R 8 , NHOR 9 , COOR 9 , CN, CONR 10 R 11 , CHO, F, Cl, Br, SO 2 NR 12 R 13 , lower alkoxy, OCF 3 , mono-, di or trifluoromethyl； R 3 and R 4 are, independently of each other, H, a saturated or unsaturated, linear or branched aliphatic radical having 1-3 chain members, F, Cl, Br, lower alkoxy； R 5 is H, a saturated or unsaturated, halogenated or unhalogenated, linear or branched aliphatic radical having 1-7 chain members； R 6 is a radical: wherein X is saturated or unsaturated, halogenated or unhalogenated, linear or branched aliphatic radical having 1-5 chain members, or R 5 and R 6 together represent bivalent radicals wherein n is 1-4: R 7 - R 13 are, independently of each other H or a saturated or unsaturated, halogenated or unhalogenated, linear or branched aliphatic radical having 1-5 chain members, phenyl, benzyl or R 7 and R 8 together, R 10 and R 11 together, R 12 and R 13 together represent a linear or branched aliphatic bivalent radical having 1-7 chain members； R 14 and R 15 are, independently of each other, H, linear or branched aliphatic radical having 1-5 chain members, F, Cl, Br, NO 2 , NH 2 , CF 3 .
