| abstract |
A compound of formula (I) wherein: A represents a benzo ring, a six membered heterocyclic aromatic ring having 1 to 3 nitrogen atoms, or a five membered heterocyclic aromatic ring having 1 to 3 heteroatoms which may be the same or different and are selected from O, N and S; R2 and R3 independently represent hydrogen, alkyl, alkoxy, alkylthio, halogen, hydroxy or amino; R1 represents: (i) phenyl, a six membered heterocyclic aromatic ring having 1 to 3 nitrogen atoms, or a five membered heterocyclic aromatic ring having 1 to 3 heteroatoms which may be the same or different and are selected from O, N and S, the phenyl or heterocyclic aromatic ring being unsubstituted or substituted by alkyl, alkoxy, alkylthio, alkenyl, alkynyl, haloalkyl, alkoxyalkyl, alkylthioalkyl, amino, halogen, hydroxy, cyano or nitro; or (ii) OR4, where R4 represents alkyl, alkenyl, alkynyl, haloalkyl, alkoxyalkyl, alkylthioalkyl, arylalkyl or aryloxyalkyl; X represents CH2, CO, O or S(O)n where n represents an integer from 0 to 2; or a pharmaceutically acceptable salt, enantiomer or tautomer thereof. The compounds are useful for treating or reducing the risk of human diseases or conditions in which inhibition of nitric oxide synthase activity, including asthma or rheumatoid arthritis. |