La presente se refiere a compuestos de isonicotinamida que son antagonistas de los receptores de orexina, y que son utiles en el tratamiento o prevencion de trastornos y enfermedades neurologicas y psiquiátricas en las que están implicados los receptores de orexina. La presente también se refiere a composiciones farmacéuticas que comprenden estos compuestos y al uso de estos compuestos y composiciones en la prevencion o tratamiento de dichas enfermedades en las que están implicados los receptores de orexina. Reivindicacion 1: Un compuesto que se selecciona entre el grupo que consiste en: N-[(5,6-dimetoxipiridin-2-il)metil]-6-(2-fluorofenil)-5'-metil-3,3'-bipiridin-5-carboxamida; N-(3,4-dimetoxibencil)-2,5bis(3,5-dimetilfenil)isonicotinamida; N-(3,4-dimetoxibencil)-6-(3,5-dimetilfenil)-3,3'-bipiridin-4-carboxamida; N(3,4-dimetoxibencil)-2-(3,5-dimetilfenil)-5-(1-metil-1H-pirazol-4-il)isonicotinamida; N-(3,4-dimetoxibencil)-5-metil-3,2',5',3ö-terpiridin-4'-carboxamida; 6-(3-cloro-5-metilfenil)-N-(3,4-dimetoxibencil)-3,3'-bipiridin-4-carboxamida; N-[(5,6-dimetoxipiridin-3-il)metil]-2-(3,5-dimetilfenil)-5-fenilisonicotinamida; 5ö-cloro-N-[(5,6-dimetoxipiridin-2-il)metil]-2,3':6',3ö-terpiridin-4'-carboxamida; N-[(5,6-dimetoxipirazin-2-il)metil]-5-(3-fluorofenil)-5'-metil-2,3'-bipiridin-4-carboxamida; N-(3-ciclopropil-4-metoxibencil)-5-(3-fluorofenil)-5'-metil-2,3'-bipiridin-4-carboxamida; N-[(5,6-dimetoxipiridin-2-il)metil]-5-(2-fluorofenil)-5'-metil-2,3'-bipiridin-4-carboxamida; N-[(5,6-dimetoxipiridin-2-il)metil]-5-(3-fluorofenil)-5'-metil-2,3'-bipiridin-4-carboxamida; 5-(3-fluorofenil)-N-[4-metoxi-3-(trifluorometil)bencil]-5'-metil-2,3'-bipiridin-4-carboxamida; N-(3-cloro-4-metoxibencil)-5-(3-fluorofenil)-5'-metil-2,3'-bipiridin-4-carboxamida; N-[(5,6-dimetoxipiridin-2-il)metil]-5'-metil-5-pirazin-2-il-2,3'-bipiridin-4-carboxamida; N-[(5,6-dimetoxi-2-piridinil)metil]-5'-metil-5-(1-pirrolidinil)-2,3'-bipiridin-4-carboxamida; 5-azetidin-1-il-N-[(5,6-dimetoxipiridin-2-il)metil]-5'-metil-2,3'-bipiridin-4-carboxamida; N-[(5,6-dimetoxipiridin-2-il)metil]-5'-metil-5-(1,3-tiazol-2-il)-2,3'-bipiridin-4-carboxamida; 5'-cloro.-N-[(5,6-dimetoxipiridin-2-iI)metil]-5-(1,3-tiazol-2-il)-2,3'-bipiridin-4-carboxamida; N-[(5-ciclopropil-6-metoxipiridin-2-il)metil]-5'-metil-5-(1,3-tiazol-2-il)-2,3'-bipiridin-4- carboxamida; N-(3-cloro-4-metoxibencil)-5'-metil-5-(5-metil-1,3-tiazol-2-il)-2,3'-bipiridin-4-carboxamida; N-(3-etil-4-metoxibencil)-5'-metil-5-(4-metil-1,3-tiazol-2-il)-2,3'-bipiridin-4-carboxamida; o una sal farmacéuticamente aceptable de los mismos.This refers to isonicotinamide compounds that are antagonists of orexin receptors, and that are useful in the treatment or prevention of neurological and psychiatric disorders and diseases in which orexin receptors are involved. This also refers to pharmaceutical compositions comprising these compounds and the use of these compounds and compositions in the prevention or treatment of said diseases in which orexin receptors are involved. Claim 1: A compound selected from the group consisting of: N - [(5,6-dimethoxypyridin-2-yl) methyl] -6- (2-fluorophenyl) -5'-methyl-3,3'- bipyridin-5-carboxamide; N- (3,4-dimethoxybenzyl) -2,5bis (3,5-dimethylphenyl) isonicotinamide; N- (3,4-dimethoxybenzyl) -6- (3,5-dimethylphenyl) -3,3'-bipyridin-4-carboxamide; N (3,4-dimethoxybenzyl) -2- (3,5-dimethylphenyl) -5- (1-methyl-1 H -pyrazol-4-yl) isonicotinamide; N- (3,4-dimethoxybenzyl) -5-methyl-3,2 ', 5', 3ö-terpyridin-4'-carboxamide; 6- (3-Chloro-5-methylphenyl) -N- (3,4-dimethoxybenzyl) -3,3'-bipyridin-4-carboxamide; N - [(5,6-dimethoxypyridin-3-yl) methyl] -2- (3,5-dimethylphenyl) -5-phenylisonicotinamide; 5ö-Chloro-N - [(5,6-dimethoxypyridin-2-yl) methyl] -2,3 ': 6', 3ö-terpyridin-4'-carboxamide; N - [(5,6-dimethoxypyrazin-2-yl) methyl] -5- (3-fluorophenyl) -5'-methyl-2,3'-bipyridine-4-carboxamide; N- (3-cyclopropyl-4-methoxybenzyl) -5- (3-fluorophenyl) -5'-methyl-2,3'-bipyridin-4-carboxamide; N - [(5,6-dimethoxypyridin-2-yl) methyl] -5- (2-fluorophenyl) -5'-methyl-2,3'-bipyridin-4-carboxamide; N - [(5,6-dimethoxypyridin-2-yl) methyl] -5- (3-fluorophenyl) -5'-methyl-2,3'-bipyridin-4-carboxamide; 5- (3-fluorophenyl) -N- [4-methoxy-3- (trifluoromethyl) benzyl] -5'-methyl-2,3'-bipyridin-4-carboxamide; N- (3-Chloro-4-methoxybenzyl) -5- (3-fluorophenyl) -5'-methyl-2,3'-bipyridin-4-carboxamide; N - [(5,6-dimethoxypyridin-2-yl) methyl] -5'-methyl-5-pyrazin-2-yl-2,3'-bipyridin-4-carboxamide; N - [(5,6-dimethoxy-2-pyridinyl) methyl] -5'-methyl-5- (1-pyrrolidinyl) -2,3'-bipyridin-4-carboxamide; 5-azetidin-1-yl-N - [(5,6-dimethoxypyridin-2-yl) methyl] -5'-methyl-2,3'-bipyridin-4-carboxamide; N - [(5,6-dimethoxypyridin-2-yl) methyl] -5'-methyl-5- (1,3-thiazol-2-yl) -2,3'-bipyridin-4-carboxamide; 5'-Chloro.-N - [(5,6-dimethoxypyridin-2-iI) methyl] -5- (1,3-thiazol-2-yl) -2,3'-bipyridin-4-carboxamide; N - [(5-cyclopropyl-6-methoxypyridin-2-yl) methyl] -5'-methyl-5- (1,3-thiazol-2-yl) -2,3'-bipyridine-4-carboxamide; N- (3-Chloro-4-methoxybenzyl) -5'-methyl-5- (5-methyl-1,3-thiazol-2-yl) -2,3'-bipyridin-4-carboxamide; N- (3-ethyl-4-methoxybenzyl) -5'-methyl-5- (4-methyl-1,3-thiazol-2-yl) -2,3'-bipyridin-4-carboxamide; or a pharmaceutically acceptable salt thereof.