The present invention relates to a compound of formula (I)wherein X is NH or O Y is OH A is H or COOH B is H, CH2OH or CH2NH2 (a) ZR1R2 is isoquinolin-1-yl, said isoquinolin-1-yl being partially or fully hydrated in the N-containing ring or given by formula (II)or (b) Z is O or N R1 is (i) C1 to C6 alkyl, preferably CH3 C2 to C6 alkenyl or C2 to C6 alkynyl or (ii) arylalkyl, preferably phenylalkyl, alkyl in said arylalkyl being C1 to C4 alkyl, phenylalkyl preferably being CH2C6H5 R2 is (iii)absent in case of Z being O or (iv) H in case of Z being N.