| abstract |
A compound of formula (I) or a salt thereof: ** Formula ** in which ring A is the following formula (a), ** Formula ** R2 is C1-6 alkyl substituted with at least one selected substituent from the group consisting of -CO2H, aryl substituted with one or more -CO2H and aromatic heterocycle substituted with one or more -CO2H; or H; L1 is -C (O) -C1-6 alkylene- or -C (O) -N (R6) -; L2 is -C1-6alkylene- which may be substituted with aryl which may be substituted by at least one substituent selected from the group consisting of -CO2H and -O-C1-6alkylene-CO2H; -C 1-6 alkylene-phenylene-; - phenylene-C1-6alkylene-; or -C 1-6 alkylene-phenylene-C 1-6 alkylene-; R3 is halogen; R6 is H or C1-6 alkyl; m is 0; and p is 0. |