Immuno inhibitory pyrazolone compounds

Abstract

Compounds of formula (IA) or (IB) are inhibitors of CD80 and useful in immunomodulation therapy: wherein Ar represents an optionally substituted monocyclic or bicyclic aromatic or heteroaromatic group having from 5 to 10 ring atoms; Rand Rindependently represent H, or C-Calkyl; Rrepresents H; F; CI; Br, —NO; —CN; C-Calkyl optionally substituted by F or CI; or C-Calkoxy optionally substituted by F; Rrepresents a carboxylic acid group (—COOH) or an ester thereof, or —C(═O)NRR, —NRC(═O)R, —NRC(═O)OR, —NHC(═O)NRRor —NHC(═S)NRRwherein Rrepresents H, or a radical of formula -(Alk)-Q wherein m is 0 or 1, Alk is an optionally substituted divalent straight or branched C-Calkylene, or C-Calkenylene, or C-Calkynylene radical or a divalent C-Ccarbocyclic radical, any of which radicals may be interrupted by one or more —O—, —S— or —N(R)— radicals wherein Rrepresents H or C-Calkyl, C-Calkenyl, C-Calkynyl, or C-Ccycloalkyl, and Q represents H; —CF; —OH; —SH; —NRRwherein each Rmay be the same or different, or form a ring when taken together with the nitrogen to which they are attached; an ester group; or an optionally substituted aryl, aryloxy, cycloalkyl, cycloalkenyl or heterocyclic group; and Rrepresents H or C-Calkyl; or when taken together with the atom or atoms to which they are attached Rand Rform a monocyclic heterocyclic ring having 5, 6 or 7 ring atoms; and X represents a bond or a divalent radical of formula -(Z)-(Alk)- or -(Alk)-(Z)- wherein Z represents —O—, —S— or —NH—, Alk is as defined in relation to Rand n is 0 or 1.