The present invention concerns a compound of following formula (I): where: - R 1 is H or OH, - R 2 is a (C 1 -C 6 )alkyl, COOH, COO-((C 1 -C 6 )alkyl) or thiazolyl group, - R 3 is H or a (C 1 -C 6 )alkyl group, and - R 4 is: –ª a straight-chain or branched, saturated or unsaturated hydrocarbon group having 1 to 8 carbon atoms substituted by one or more groups chosen from among OH and NR 5 R 6 , –ª -(CH 2 CH 2 X 1 )(CH 2 CH 2 X 2 ) a2 (CH 2 CH 2 X 3 ) a3 (CH 2 CH 2 X 4 ) a4 (CH 2 CH 2 X 5 ) a5 P 7 , –ª an aryl-(C 1 -C 8 )alkyl group substituted by one or more groups chosen from among OH and NR 9 R 10 groups, or –ª a heterocycle-(C 1 -C 8 )alkyl group optionally substituted by one or more groups chosen from among (C 1 -C 6 )alkyl, OH and NR 12 R 13 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.
