Abstract: Compounds of formula (I), where: R0 is (C8-C11)-branched alkyl, CH3—(CH2)m—, CH3—O—(CH2CH2O)2CH2—, or phenyl-(CH2)x—; m=6-10; x=1-3; R1, R3, R4, R7, and R8 are independently selected from the formula GF-(CH2)n—; with n=1-4; and GF=—NH2 or —NH—C(?NH)—NH2; R2 is —CH(CH3)(OH), —CH(CH3)2, —CH2NH2 o —CH2OH; R5 and R6 are independently selected among H, —(C1-C4)— linear or branched alkyl, —(CH2)—R10, —CH2—CH2—S—CH3 and —CH—(CH3)—OH; R9 is CONH2, —CH(CH3)(OH) or CONHR11; R10 is phenyl, 3-indolyl, 4-imidazolyl, 4-hydroyiphenyl, ? o ?-naphtyl or 2-, 3- or 4-pyridyl; R11 is a specific peptide sequence; u is CH2 or S; v is NH o S; w is CH2 or CO; with the condition that when R9 is CONH2, then (a) R5 or R6 is —CH(CH3)(OH), or (b) R5 and R6 are H; or (c) the configuration of the C bound to R9 is S or (d) the configuration of the C bound to R5 is R; and with the condition that when R9 is —CH(CH3)OH, then R8 is GF(CH2)n where n is 3 and GF is —NH—C(?NH)—NH2, and R7 is GF(CH2)n where n is 2 and GF is NH2, have been found to