A compound of the formula I: R-A-Gly-His-B (I) wherein: A and B areindependently of each other a L-lysineresidue, a D-lysine residue, or a L- or D- lysine residue in which the NH2group of the side chain comprises a modification, whereinsaid modification is (i) a replacement with a hydrogen, (ii) an acetylation,(iii) a benzoylation, or (iv) a palmitoylation; GIy is aglycine residue; His is a L- or D-histidine residue; R is CH3-(CH2)n-CO-,wherein n = 2, 3, 4, 5, 6, 7 or 8; R' is a group of formula(II): N(Z)(Z') (II) wherein: Z and Z' is hydrogen, a methyl group, an ethylgroup, a phenyl group, an hexyl group, a decyl group oran hexadecyl group; or a racemate, an enantiomer or a diastereomer thereof, ormixtures thereof, or a salt thereof.