Substituted thiazolopyrimidines as xanthine oxidase inhibitors

Compounds of the following formula (I) or salts thereof

• in which
• R1 represents an alkyl group having 1-8 carbon atoms, an alkyl group substituted with 1-3 halogen atoms, OR4, CO2R5, or;
• S(O)nR6 wherein R4 is hydrogen, or an alkyl group having 1-8 carbon atoms, an aralkyl group having an aryl moiety of 6-10 carbon atoms and an alkyl moiety of 1-4 carbon atoms, an alkylcarbonyl group having 2-9 carbon atoms, an arylcarbonyl group having an aryl moiety of 6-10 carbon atoms, an aralkylcarbonyl group having an aryl moiety of 6-10 carbon atoms and an alkylcarbonyl moiety of 2-5 carbon atoms or an aryl group having 6-10 carbon atoms which may have a substituent selected from the group consisting of halogen, hydroxyl, nitro and cyano;
• each of R5 and R6 is hydrogen or an alkyl group having 1-8 carbon atoms, an aralkyl group having an aryl moiety of 6-10 carbon atoms and an alkyl moiety of 1-4 carbon atoms, or an aryl group having 6-10 carbon atoms which may have a substituent selected from the group consisting of halogen, hydroxyl, nitro, cyano and amino;
• and n is an integer of 0 to 2;
• R2 is hydrogen, halogen, nitro, cyano, formyl, an alkyl group having 1-8 carbon atoms, an alkyl group having 1-8 carbon atoms which is substituted with one to three halogens, or CO2R7 wherein R7 has the same meaning as R5 above;
• R3 is hydrogen, halogen, hydroxyl, amino, CO2R8, PO(OH)(OR9), S(O)mR10, or an alkyl group having 1-8 carbon atoms or an alkylaminocarbonyl group having alkyl of 1-8 carbon atoms which may have a substituent selected from the group consisting of halogen, hydroxyl, nitro, cyano and amino;
• wherein each of R8, R9, and R10 has the same meaning as R5 above;
• m has the same meaning as n above;
• X is sulfur;
• and
• each of Y and Z is nitrogen.