Patent ID: 6846930

Claim:
A compound of the formula 4: wherein R 1 is phenyl optionally substituted by 1-3 substituents independently selected from the group consisting of halo, hydroxy, cyano, mercapto, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 1 -C 6 )alkoxy, —OCF 3 , (C 1 -C 6 )alkyl-S—, (C 1 -C 6 )alkyl-S(═O)—, (C 1 -C 6 )alkyl-SO 2 —, amino, (C 1 -C 6 )alkylamino, di[(C 1 -C 6 )alkyl]amino, H 2 N—(C═O)—, (C 1 -C 6 )alkyl-NH—(C═O)— and formyl; R 2 is hydrogen, halo or (C 1 -C 6 )alkyl; R 3 is (C 1 -C 6 )alkyl optionally substituted with one to three halo atoms; and R 4 is (C 1 -C 6 )alkyl.