Chemical compounds

A compound of formula (I):

• wherein:
• R1 is phenyl which is optionally substituted by halogen, C1-4 alkyl, C1-4 haloalkyl, C1-4 alkoxy, C1-4 haloalkoxy, nitro or cyano;
• R2, R3 and R4 are, independently, hydrogen or C1-4 alkyl;
• R5 is C1-6 alkyl, aryl, heteroaryl, aryl(C1-4)alkyl, heteroaryl(C1-4)alkyl or C3-8 cycloalkyl;
• wherein the aryl and heteroaryl moieties of R5 are optionally substituted by halogen, C1-6 alkyl (optionally substituted by halogen, C1-6 alkoxy or phenyl (itself optionally substituted by halogen, C1-4 alkyl, C1-4 alkoxy or CF3)), OR6, S(O)mR7, S(O)2NR8R9, NR10S(O)2R11, C(O)R12, C(O)NR13R14, NR15C(O)R16, NR17R18, NR19C(O)NR20R21, methylenedioxy, nitro or cyano;
• X is (CH2)n, where n is 1, 2, 3 or 4;
• Y is a 2,4-, 2,5- or 3,5-linking 5-membered heteroaryl ring having 2 or 3 heteroatoms independently selected from the group consisting of nitrogen, oxygen and sulphur, wherein Y is optionally substituted by C1-4 alkyl;
• R6, R8, R9, R10, R13, R14, R15, R16, R17, R18, R19, R20 and R21 are independently, hydrogen or C1-6 alkyl (optionally substituted by C1-6 alkoxy (provided no acetal or aminal is formed) or phenyl (itself optionally substituted by halogen, C1-4 alkyl, C1-4 alkoxy or CF3));
• R7 and R11 are, independently, C1-6 alkyl (optionally substituted by C1-6 alkoxy (provided no thioacetal is formed) or phenyl (itself optionally substituted by halogen, C1-4 alkyl, —C1-4 alkoxy or CF3));
• R12 is hydrogen, C1-6 alkyl (optionally substituted by C1-6 alkoxy (provided no acetal is formed) or phenyl (itself optionally substituted by halogen, C1-4 alkyl, C1-4 alkoxy or CF3)) or C1-6 alkoxy (unsubstituted or mono-substituted by C1-6 alkoxy or phenyl (itself optionally substituted by halogen, C1-4 alkyl, C1-4 alkoxy or CF3));
• or a pharmaceutically acceptable salt thereof.