In another embodiment of formula [I-3], R1 is methyl group and R2 may be selected from the following: a ???CN group; a ???COOH group; a ???CONH2 group; a ???CONHOH group; a ???CH2OCH2COOH group; a ???CH???CHCOOH group; a ???CONHCH2COOH group; a ???CONH(CH2)2COOH group; a ???CONHCH2CONH2 group; a ???CONH(CH2)2CN group; or a group selected from the following: In the above, R3 is a hydrogen atom, R5