A compound selected from the following compounds: 3-(4-chlorophenyl)-1-(2,2-difluoroethyl)quinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-cyclopropyl-quinoxalin-2(1 H)-one 1-butyl-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 3-(4-fluorophenyl)-1-(2,2,2-trifluoroethyl)quinoxalin-2(1 H)-one 1-ethyl-6,7-difluoro-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-ethyl-6,7-difluoro-3-(4-chlorophenyl)quinoxalin-2(1 H)-one 1-cyclopropyl-3-phenylquinoxalin-2(1 H)-one 1-ethyl-3-furan-2-yl-quinoxalin-2(1 H)-one 1-ethyl-5-fluoro-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-cyclopropyl-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-butyl-3-(4-chlorophenyl)quinoxalin-2(1 H)-one 3-(4-chlorobenzyl)-1-ethyl-quinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-(2,2,2-trifluoroethyl)quinoxalin-2(1 H)-one 1-(2,2,2-trifluoroethyl)-3-(4-trifluoromethylphenyl)quinoxalin-2(1 H)-one 1-(2,2-difluoroethyl)-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-ethyl-5-fluoroquinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 3-(2-chlorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-methylphenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-fluoro-2-methylphenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-chloro-2-methylphenyl)quinoxalin-2(1 H)-on 1-ethyl-3-(4-trifluoromethylphenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-methanesulfonyl-phenyl)quinoxalin-2(1 H)-one 3-(2,4-dimethoxy-pyrimldin-5-yl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-(4-ethylphenyl)quinoxalin-2(1 H)-on 1-ethyl-3-furan-3-yl-quinoxalin-2(1 H)-one 3-(3,4-dimethoxyphenyl)-1-ethyl-quinoxalin-2(1 H)-one 4-(4-ethyl-3-oxo-3,4-dihydro-quinoxalin-2-yl)-benzoic acid 1-ethyl-3-(1-methyl-1H-pyrazol-4-yl)quinoxalin-2(1 H)-one 3-(3-chlorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-pyridin-3-yl-quinoxalin-2(1 H)-one 3-(2,5-difluorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-(1H-indol-6-yl)quinoxalin-2(1 H)-one 1-ethyl-3-(1H-indol-5-yl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-methylbenzyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-morpholin-4-ylphenyl)quinoxalin-2(1 H)-one 3-(2,3-dihydro-1,4-benzodioxin-6-yl)-1-ethylquinoxalin-2(1 H)-one 3-(1,3-benzodioxol-5-yl)-1-ethylquinoxalin-2(1 H)-one 1-ethyl-3-benzylquinoxalin-2(1 H)-one as well as its racemic forms, tautomers, enantiomers, diastereomers, epimers and polymorphs, and mixtures thereof, and the pharmaceutically acceptable salts thereof. 3-(4-chlorophenyl)-1-(2,2-difluoroethyl)quinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-cyclopropyl-quinoxalin-2(1 H)-one 1-butyl-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 3-(4-fluorophenyl)-1-(2,2,2-trifluoroethyl)quinoxalin-2(1 H)-one 1-ethyl-6,7-difluoro-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-ethyl-6,7-difluoro-3-(4-chlorophenyl)quinoxalin-2(1 H)-one 1-cyclopropyl-3-phenylquinoxalin-2(1 H)-one 1-ethyl-3-furan-2-yl-quinoxalin-2(1 H)-one 1-ethyl-5-fluoro-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-cyclopropyl-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-butyl-3-(4-chlorophenyl)quinoxalin-2(1 H)-one 3-(4-chlorobenzyl)-1-ethyl-quinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-(2,2,2-trifluoroethyl)quinoxalin-2(1 H)-one 1-(2,2,2-trifluoroethyl)-3-(4-trifluoromethylphenyl)quinoxalin-2(1 H)-one 1-(2,2-difluoroethyl)-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-ethyl-5-fluoroquinoxalin-2(1 H)-one 3-(4-chlorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 3-(2-chlorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-(4-fluorophenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-methylphenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-fluoro-2-methylphenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-chloro-2-methylphenyl)quinoxalin-2(1 H)-on 1-ethyl-3-(4-trifluoromethylphenyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-methanesulfonyl-phenyl)quinoxalin-2(1 H)-one 3-(2,4-dimethoxy-pyrimldin-5-yl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-(4-ethylphenyl)quinoxalin-2(1 H)-on 1-ethyl-3-furan-3-yl-quinoxalin-2(1 H)-one 3-(3,4-dimethoxyphenyl)-1-ethyl-quinoxalin-2(1 H)-one 4-(4-ethyl-3-oxo-3,4-dihydro-quinoxalin-2-yl)-benzoic acid 1-ethyl-3-(1-methyl-1H-pyrazol-4-yl)quinoxalin-2(1 H)-one 3-(3-chlorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-pyridin-3-yl-quinoxalin-2(1 H)-one 3-(2,5-difluorophenyl)-1-ethyl-quinoxalin-2(1 H)-one 1-ethyl-3-(1H-indol-6-yl)quinoxalin-2(1 H)-one 1-ethyl-3-(1H-indol-5-yl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-methylbenzyl)quinoxalin-2(1 H)-one 1-ethyl-3-(4-morpholin-4-ylphenyl)quinoxalin-2(1 H)-one 3-(2,3-dihydro-1,4-benzodioxin-6-yl)-1-ethylquinoxalin-2(1 H)-one 3-(1,3-benzodioxol-5-yl)-1-ethylquinoxalin-2(1 H)-one 1-ethyl-3-benzylquinoxalin-2(1 H)-one as well as its racemic forms, tautomers, enantiomers, diastereomers, epimers and polymorphs, and mixtures thereof, and the pharmaceutically acceptable salts thereof.