Abstract: A compound of formula (I), wherein R1 is H; R2 is aryl, het, C3-8cycloalkyl, C1-6alkyl, (CH2)2aryl or R4, wherein each of the cycloalkyl, aryl, het and R4 groups is optionally substituted by at least one substituent independently selected from C1-6alkyl, C1-6alkoxy, OH, halo, CF3, OCF3, OCHF2, O(CH2)yCF3, CN, CONH2, CON(H)C1-6alkyl, CON(C1-6alkyl)2, hydroxy-C1-6alkyl, C1-4alkoxy-C1-6alkyl, C1-4alkoxy-C1-4alkoxy, SCF3, C1-6alkyISO2, C1-4alkyl-S-C1-4alkyl, C1-4alkyl-S—, C1-4alkyINR10R11 and NR10R11; or R1 and R2, together with the carbon atom to which they are bound, form a 5- or 6-membered carbocycle or a 5- or 6-membered heterocycle containing at least one N, O or S heteroatom; R3 is aryl, het or R4, each optionally substituted by at least one substituent independently selected from C1-6-alkyl, C1-6-alkoxy, het, OH, halo, CF3, OCF3, OCHF2, O(CH2)yCF3, CN, CONH2, CON(H)C1-6alkyl, CON(C1-6alkyl)2, hydroxy-C1-6alkyl, C1-4alkoxy-C1-6alkyl, C1-4alkoxy-C1-4alkoxy, SCF3, C1-6alkyISO2, C1-4alkyl-S-C1-4alkyl, C1-4alky