Patent ID: 8809558

Claim:
A compound of formula 1: wherein: R a is H, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 3 -C 8 )cycloalkyl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, aryl, or heteroaryl, wherein each (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 3 -C 8 )cycloalkyl, and (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl of R a is optionally substituted with one or more groups independently selected from halo, hydroxy, cyano, nitro, (C 1 -C 6 )alkoxy, (C 3 -C 8 )cycloalkyl, oxo, carboxy, aryl, aryloxy, and —NR b R c ; and wherein each aryl, and heteroaryl of R a is optionally substituted with one or more groups independently selected from (C 1 -C 6 )alkyl, halo, hydroxy, cyano, carboxy, nitro, trifluoromethyl, trifluoromethoxy, (C 1 -C 6 )alkoxy, (C 1 -C 6 )alkoxycarbonyl, (C 1 -C 6 )alkanoyloxy, and —NR b R c ; and R b and R c are each independently selected from H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, (C 3 -C 8 )cycloalkyl(C 1 -C 6 )alkyl, aryl, heteroaryl, aryl(C 1 -C 6 ) alkyl and heteroaryl(C 1 -C 6 )alkyl; or R b and R c together with the nitrogen to which they are attached form a aziridino, azetidino, morpholino, piperazino, pyrrolidino or piperidino.