Amide compounds (I) and their salts, isomers or mixtures of isomers in all proportions, including mixture of enantiomer and racemic mixture are new. Amide compounds of formula (R1-N(R2)-C(=O)-C(R3)(R4)-N(R5)-C(=O)-R6) (I) and their salts, isomers or mixtures of isomers in all proportions, including mixture of enantiomer and racemic mixture are new. Either R1 : H, (1-6C)alkyl, (3-10C)cycloalkyl, (3-10C)cycloalkenyl, aryl, heteroaryl, aryl-(1-6C)alkyl or heteroaryl-(1-6C)alkyl (all optionally substituted by one or more groups comprising halo, (1-6C)alkoxy, -NH 2, -COOH, -CN, -OH, -NR7R8, -O-(1-6C)alkyl-NR7R8, benzyloxy, aryloxy,-C(O)O-(1-6C)alkyl, -NH-C(O)O-(1-6C)alkyl, -C(O)NH 2, -C(O)NR9R10, -S-(1-6C)alkyl, -S(O)-(1-6C)alkyl, -SO 2-(1-6C)alkyl, -SO 2NH 2, -O 2NR11R12, -NR13SO 2R14 or (1-6C)alkyl (optionally substituted by one or more halo)) and R2 : H or (1-6C)alkyl, preferably (1-4C)alkyl or N+R1R2 : heteroaryl (optionally substituted by one or more groups comprising halo, -CN, -NH 2, -NR40R41, -NO 2, -OH, (1-6C)alkoxy, aryloxy, benzyloxy, -O(1-6C)alkyl-NR42R43, -C(O)O-(1-6C)alkyl, -NHC(O)O-(1-6C)alkyl-C(O)NH 2, -C(O)NR44R45, -SO 2NH 2, -SO 2NR46R47 or NR48SO 2R49) or heterocyclic ring of 3-7 members (optionally substituted by one or more groups comprising halo, (3-10C)cycloalkyl, (3-10C)cycloalkenyl, aryl, heteroaryl, aryl-(1-6C)alkyl, heteroaryl-(1-6C)alkyl, heterocycloalkyl-(1-6C)alkyl, -OH, -NH 2, -C(O)OH, -C(O)NH 2, -C(S)NH 2, -OR50, -OC(O)R51, -C(O)R52, -C(O)OR53, -NHC(O)R54, -NHC(O)OR55, -SO 2R56, -(1-6C)alkyl, -C(O)OR57, -NR58R59, -C(O)NR60R61, -C(O)N(R62)(aryl), C(O)N(R63)(heteroaryl), -C(O)NHNR64R65, -C(S)NR66R67, C(S)N(R68)(aryl), -C(S)N(R69)(heteroaryl), -C(S)NHNR70R71, -OC(O)-NR72R73, -(1-6C)alkyl-C(O)-NR74R75, -(1-6C)alkyl-NR103-C(O)-OR104, -(1-6C)alkyl-NR76R77, -C(NOR78)-aryl or (1-6C)alkyl (optionally substituted by one or more halo)), where aryl and heteroaryl radical are optionally substituted by one or more groups comprising halo, -CN, -OH, (1-6C
