SRS-A antagonists

Abstract

There are described pharmacologically active compounds, useful in the treatment of allergic/inflammatory disorders involving SRS-A as causal mediator and which, in free acid form, are of formula I, ##STR1## in which R.sub.1 is (i) an aliphatic, saturated or unsaturated hydrocarbyl radical of up to 20 carbon atoms, unsubstituted or substituted by at least one substituent selected from halogen, hydroxy, C.sub.3-6 alkoxy, C.sub.3-6 cycloalkyl, aryl or heteroaryl, the cycloalkyl, aryl or heteroaryl being unsubstituted or substituted by at least one substituent selected from hydroxy, halogen and alkyl, alkenyl or alkynyl of up to 10 carbon atoms, (ii) cycloalkyl of 3 to 8 carbon atoms unsubstituted or substituted by alkyl, alkenyl or alkynyl of up to 16 carbon atoms, or (iii) aryl or heteroaryl, unsubstituted or substituted by hydroxyl, C.sub.1-4 alkoxy, halogen or alkyl, alkenyl or alkynyl of up to 16 carbon atoms; and R.sub.2 is (i) alkyl, cycloalkyl or alkenyl of up to 10 carbon atoms, unsubstituted or substituted by one or more substituents selected from aryl, cycloalkyl, halogen, hydroxy, NHR.sub.3 and COX, where R.sub.3 is H, C.sub.1-4 alkyl, aryl or an amino acid residue or COX, and X is OH, C.sub.1-4 alkyl, NH.sub.2 or an amino acid residue, or (ii) aryl or heteroaryl, unsubstituted or substituted by one or more substituents selected from C.sub.1-4 alkyl, C.sub.1-4 alkoxy, C.sub.2-5 acyl, halogen, hydroxy, carboxy, nitro, trihalomethyl, phenyl, C.sub.1-4 acylamino and NHR.sub.4, where R.sub.4 is hydrogen or C.sub.1-4 alkyl; and Y is --S--, --SO-- or --SO.sub.2 --, with the proviso that when --YR.sub.2 is glutathionyl, cysteinyl or cysteinylglycinyl, then R.sub.1 is other than an unsubstituted alkatetraenyl or alkapentaenyl radical of 12 to 16 carbon atoms.

Dependencies are inferred from the claim text.