7-substituted sulfonimidoylpurinone compounds and derivatives for the treatment and prophylaxis of liver cancer

A method for the treatment or prophylaxis of liver cancer comprising administering to a patient in need thereof, a therapeutically effective amount of a compound of formula (I), or a pharmaceutically acceptable salt, enantiomer or diastereomer thereof,

• wherein:
• R1 is C1-6alkyl;
• R2 is benzyl, said benzyl being unsubstituted or substituted by one, two or three substituents independently selected from halogen and C1-6alkyl;
• R3 is —NR4R5, wherein
• R4 is C1-6-alkyl or C1-6alkoxyC1-6alkyl;
• R5 is (C1-6alkyl)2NCOOC1-6alkyl, C1-6alkoxyC1-6alkyl, C1-6alkoxycarbonyl(C1-6alkyl)aminoC1-6 alkyl, C1-6alkoxycarbonyl(phenyl)C1-6alkyl, C1-6alkoxycarbonylC1-6alkyl, C1-6 alkoxycarbonyloxyC1-6alkyl, C1-6alkyl, C1-6alkylcarbonyl(C1-6alkyl)aminoC1-6alkyl or pyrrolidinylcarbamoyloxyC1-6alkyl;
• or
• R4 and R5 together with the nitrogen they are attached to form a heterocyclyl;
• with the proviso that the compound is not:
• 6-amino-9-benzyl-2-(propylsulfonimidoyl)-7-(pyrrolidine-1-carbonyl)purin-8-one;
• 6-amino-9-benzyl-7-(piperidine-1-carbonyl)-2-(propylsulfonimidoyl)purin-8-one;
• 6-amino-9-benzyl-7-(morpholine-4-carbonyl)-2-(propylsulfonimidoyl)purin-8-one;
• 6-amino-9-benzyl-7-(3,3-dimethylpyrrolidine-1-carbonyl)-2-(propylsulfonimidoyl)purin-8-one;
• ethyl 1-[6-amino-9-benzyl-8-oxo-2-(propylsulfonimidoyl)purine-7-carbonyl]pyrrolidine-2-carboxylate;
• 6-amino-7-(2-azaspiro[3.3]heptane-2-carbonyl)-9-benzyl-2-(propylsulfonimidoyl)purin-8-one;
• 6-amino-9-benzyl-7-(2-oxa-6-azaspiro[3.3]heptane-6-carbonyl)-2-(propylsulfonimidoyl)purin-8-one;
• 6-amino-9-benzyl-7-(3,3-difluoropyrrolidine-1-carbonyl)-2-(propylsulfonimidoyl)purin-8-one;
• or
• 6-amino-9-benzyl-7-(3-fluoro-3-methyl-pyrrolidine-1-carbonyl)-2-(propylsulfonimidoyl)purin-8-one;
• or an enantiomer or diastereomer thereof.