| abstract |
Anthranilic acids of formula (I): n wherein each of R to R 9 is an organic substituent, n is 0 or 1, m is 0 or an integer of 1 to 6, q is 0 or 1, X is a direct bond, O, S, —S—(CH 2 ) p or —O—(CHO 2 ) p — wherein p is from 1 to 6 and Ar is an unsaturated carbocyclic or heterocyclic group, and the pharmaceutically acceptable salts thereof, have activity as inhibitors of P-glycoprotein and may thus be used, inter alia, as modulators of multidrug resistance in the treatment of multidrug resistant cancers, for example to potentiate the cytotoxicity of a cancer drug. |