Patent ID: 7919503

Claim:
A compound of the general formula: wherein, R 1 is a mono- or bicycloalkylalkyl group or mono- or bicycloalkyl group; R 2 is selected from straight or branched C 1 -C 5 alkyl which may optionally substituted with —OH, —CH 2 —OH, C 1 -C 5 alkoxy, NH 2 —, N(R a ) 2 —, NHR a —, CN—, CF 3 , halogen (i.e. Cl, F, Br or I), piperidino, morpholino, pyrrolidino, 5H-tetrazolylpropyl, methylcarbamoyl, dimethylcarbamoyl, or ethylmethylcarbamoyl, wherein R a is C 1 -C 5 alkyl; R 3 , R 4 , R 5 , R 6 are at each occurrence independently selected from hydrogen, halogen (i.e. Cl, F, Br or I), methyl, methoxy, cyano, or trifluoromethyl; a, b, c, d, x are at each occurrence independently selected from carbon, or nitrogen; or a pharmaceutically acceptable salt thereof.