7-imino derivatives of camptothecin having antitumor activity

A method for treating a subject suffering from a tumor selected from the group consisting of non-small cell lung tumor and gastric cancer comprising administering to said subject a compound of formula (I)

• wherein:
• R1 is a —C(R5)═N—R4 group, wherein R4 is a phenyl group substituted with one or more keto groups;
• —S—S-(2-aminophenyl), —S—S-(4-aminophenyl), —S-(4-aminophenyl), —SCH3 and —CH2ON═C(CH3)2;
• R5 is hydrogen, C1-C8 linear or branched alkyl, C1-C8 linear or branched alkenyl, C3-C10 cycloalkyl, (C3-C10) cycloalkyl-(C1-C8) linear or branched alkyl, C6-C14 aryl, (C6-C14) aryl-(C1-C8) linear or branched alkyl;
• R2 and R3, the same or different between them are hydrogen, hydroxy, C1-C8 linear or branched alkoxy;
• their N1-oxides, their single isomers, in particular the syn and anti isomers of the —C(R5)═N—R4 group, their possible enantiomers, diastereoisomers and relative admixtures, and the pharmaceutically acceptable salts thereof.