A compound having the general Formula wherein, R 1 is H, (C 1 -C 6)-alkyl or aryl; or alternatively R 1 and one R 4, each being linked to two adjacent carbon atoms, in case n is 2 or 3, are taken together to form a cyclopropane ring; R 2 is phenyl optionally substituted with halogen, benzyloxy, (C 1 -C 3)-alkyl or CF 3; (C 3 -C 6)-cycloalkyl; aryl-(C 1 -C 6)-alkyl wherein the aryl is optionally substituted with benzyloxy, (C 1 -C 3)-alkyl or CF 3; R 3 is H, PO 2, or a group of Formula - -R 7 Formula II R 7 is (C 1 -C 7)-alkyl, (C 1 -C 6)-alkoxy or -CH(NH 2) R 8; R 8 is H, or the side chain of a natural α-amino acid selected from the group consisting of glycine, alanine, phenylalanine, valine, leucine, isoleucine, aspartic acid, asparagine, glutamic acid, glutamine, serine, lysine, histidine, methionine, proline, cysteine, threonine, tryptophan, arginine and tyrosine; R 4 and R 5 are at any occurrence independently H, halogen, (C 1 -C 6)-alkyl, or alternatively, when n is 2 or 3, one R 4 and one R 5, each being linked to two adjacent carbon atoms, are taken together to form a cyclopropane ring; R 6 is H or alternatively, R 2 and R 6 are taken together to form a five- to six-membered heterocycle which can be optionally fused with an aryl moiety; -A-E- is - -(N R 9)- or -(N R 9)- -; R 9 is H or (C 1 -C 3)-alkyl; m is an integer comprised between 0 to 3; n is an integer comprised between 0 to 3 with the proviso that when is 2 or 3, each of R 4 and R 5 can adopt different meaning at each occurrence; the symbol means that the carbon atom bearing said symbol can adopt a R or S configuration; the symbol ○ can be absent, but if present it means that the cycle can be partially unsaturated with the proviso that when the carbon atom bearing R 4 is involved in a double bond, R 5 is absent; their tautomers, their geometrical isomers, their optically active forms such as enantiomers, diastereomers and their racemate forms, as well as their pharmaceutically acceptable salts thereof. R 1 is H, (C 1 -C 6)-alkyl or aryl; or alternatively R 1 and one R 4, each being linked to two adjacent carbon atoms, in case n is 2 or 3, are taken together to form a cyclopropane ring; R 2 is phenyl optionally substituted with halogen, benzyloxy, (C 1 -C 3)-alkyl or CF 3; (C 3 -C 6)-cycloalkyl; aryl-(C 1 -C 6)-alkyl wherein the aryl is optionally substituted with benzyloxy, (C 1 -C 3)-alkyl or CF 3; R 3 is H, PO 2, or a group of Formula - -R 7 Formula II R 7 is (C 1 -C 7)-alkyl, (C 1 -C 6)-alkoxy or -CH(NH 2) R 8; R 8 is H, or the side chain of a natural α-amino acid selected from the group consisting of glycine, alanine, phenylalanine, valine, leucine, isoleucine, aspartic acid, asparagine, glutamic acid, glutamine, serine, lysine, histidine, methionine, proline, cysteine, threonine, tryptophan, arginine and tyrosine; R 4 and R 5 are at any occurrence independently H, halogen, (C 1 -C 6)-alkyl, or alternatively, when n is 2 or 3, one R 4 and one R 5, each being linked to two adjacent carbon atoms, are taken together to form a cyclopropane ring; R 6 is H or alternatively, R 2 and R 6 are taken together to form a five- to six-membered heterocycle which can be optionally fused with an aryl moiety; -A-E- is - -(N R 9)- or -(N R 9)- -; R 9 is H or (C 1 -C 3)-alkyl; m is an integer comprised between 0 to 3; n is an integer comprised between 0 to 3 with the proviso that when is 2 or 3, each of R 4 and R 5 can adopt different meaning at each occurrence; the symbol means that the carbon atom bearing said symbol can adopt a R or S configuration; the symbol ○ can be absent, but if present it means that the cycle can be partially unsaturated with the proviso that when the carbon atom bearing R 4 is involved in a double bond, R 5 is absent;