Patent ID: 7820658

Claim:
A compound of formula (I), or a salt or N-oxide thereof: wherein R 2 is a group of formula (IA): —(Ar 1 ) m -(Alk 1 ) p -(Z) r -(Alk 2 ) s -Q (IA) wherein Ar 1 is an optionally substituted aryl or heteroaryl radical, Alk 1 and Alk 2 are optionally substituted divalent C 1 -C 3 alkylene or C 2 -C 3 alkenylene radicals, m, p, r and s are independently 0 or 1, Z is —O—, —S—, —(C═O)—, —(C═S)—, —SO 2 —, —C(═O)O—, —C(═O)NR A —, —C(═S)NR A —, —SO 2 NR A —, —NR A C(═O)—, —NR A SO 2 — or —NR A — wherein R A is hydrogen or C 1 -C 6 alkyl, and Q is hydrogen or an optionally substituted carbocyclic or heterocyclic radical; R 3 is hydrogen, an optional substituent, or an optionally substituted (C 1 -C 6 )alkyl, aryl or heteroaryl radical; and R 4 is a carboxylic ester, carboxamide or sulfonamide group, wherein when optionally substituted, substituent(s) is/are selected from the group consisting of (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, hydroxy, hydroxy(C 1 -C 6 )alkyl, mercapto, mercapto(C 1 -C 6 )alkyl, (C 1 -C 6 )alkylthio, halo, trifluoromethyl, trifluoromethoxy, nitro, nitrile (—CN), oxo, phenyl, —COOH, —COO R F , —CO R F , —SO 2 R F , —CONH 2 , —SO 2 NH 2 , —CONHR F , —SO 2 NHR F , —CONR F R G , —SO 2 NR F R G , —NH 2 , —NHR F , —NR F R G , —OCONH 2 , —OCONHR F , —OCONR F R G , —NHCOR F , —NHCOOR F , —NR F COOR F , —NHSO 2 OR F , NR G SO 2 OR F , —NHCONH 2 , —NR F CONH 2 , —NHCONHR G , —NR F CONHR G , —NHCONR F R G , or —NR F CONR F R G wherein R F and R G are independently a (C 1 -C 6 )alkyl group; provided that (i) R 3 is not —NH 2 and (ii) when R 4 is —COOCH 3 and R 3 is hydrogen then R 2 is not —NH 2 , ethylamino, diethylamino, phenylamino, N(Ph)(C 2 H 5 ) wherein Ph is phenyl, pyrrolidin—1—yl or morpholin—4—yl and (iii) when R 4 is —CONH 2 and R 3 is hydrogen then R 2 is not —NH 2 .