Patent ID: 7109202

Claim:
A compound of formula in free or salt form, where Ar is a C 6 –C 15 monovalent aromatic group, R 1 is hydrogen, phenyl optionally substituted by one or more substituents selected from halogen, cyano, hydroxy, C 1 –C 8 -alkyl, C 1 –C 8 -haloalkyl, C 1 –C 8 -alkoxy, C 1 –C 8 -alkoxy-C 1 –C 8 -alkyl or acyloxy, or a 5- or 6-membered monovalent heterocyclic group, R 2 is hydrogen, C 1 –C 8 -alkyl, acyl or —CON(R 3 )R 4 , provided that R 2 is C 1 –C 8 -alkyl, acyl or —CON(R 3 )R 4 when R 1 is hydrogen, R 3 and R 4 are each independently hydrogen or C 1 –C 8 -alkyl, or together with the nitrogen atom to which they are attached denote a 5- or 6-membered heterocyclic group, and Z 1 , Z 2 , Z 3 and Z 4 are each independently N or CR 5 , at least one of them being CR 5 , and R 5 is hydrogen, C 1 –C 8 -alkyl or C 1 –C 8 -alkoxy.