The present invention concerns a compound of following formula (I) where: —R1 is H or OH, —R2 is a (C1-C6)alkyl, COOH, COO—((C1-C6)alkyl) or thiazolyl group, —R3 is H or a (C1-C6)alkyl group, and —R4 is: —an aryl-(C1-C8)alkyl group substituted by one or more groups chosen from among OH and NR9R10 groups, or —a heterocycle-(C1-C8)alkyl group optionally substituted by one or more groups chosen from among (C1-C6)alkyl, OH and NR12R13 groups, or a pharmaceutically acceptable salt, hydrate or solvate thereof, and its uses in particular for the treatment of cancer, pharmaceutical compositions containing the same and the preparation methods thereof.
