abstract |
A compound of general formula I ** Formula ** where Y represents O, N, S or a covalent bond, P1 represents H, a protective group of Y or an activating group of Y or a spacer group, P2, P3 independently represent between yes H, an amino protecting group or a spacer group, or P2 and P3 form, together with the N to which they are attached, a ring structure, L is a group of formula (a) ** Formula ** where the line discontinuous represents the bond to N, R1 represents H or a group of formula - (CH2) 2-ORb1, R1 'represents H or a group of formula - (CH2) 2-ORb2, R2 represents H or a group of formula - CH2-ORc, R2 'represents H or a group of formula -ORd or -CH2-ORd, R3 represents H or a group of formula - (CH2) 2-ORe or - (CH2) 3-ORe, Ra, Rb1, Rb2 , Rc, Rd, Re independently represent each other a linear or branched, saturated or unsaturated hydrocarbon chain, m is 1, 2 or 3, with the proviso that at least one of R1, R1 ', R2, R2', R3 don't be H. |