Relates to Heterocyclic compounds of formula (i) where X1 or x2 is CR1, CR2 and Cr3 X3 and X4 is is n n or CR4, where R1 and R4 are each h, halogen, alkyl (c1-c4), among others R2 and R3 are each H Oh, (c1-c4) - alkoxy alkyl (c1-c4), among others is o, S, S, S (= o) (= o) 2, among other S Het is hetarilo monociclico phenyl bicyclic or hetarilo R7, R8, R9 and R10 are each h,Halogen, alkyl (c1-c4), fluoroalcoxi (c1-c4), among others. Preferred compounds are: 4 - pyridin-4-yl - 2 - (quinolin-2 - il - ethyl) - 1,2 Dihydro pyrrolo [3,4-c] pyridin - 3-one 7 - pyridin-4-yl - 2 - (quinolin-2 - il - ethyl) - 2,3 Dihydro pyrrolo [3,4-c] pyridin - 1 - One 3.3 - difluoro - 7 - pyridin-4-yl - 2 - (quinolin-2 - il - ethyl) - 2.3 - dihydro - 1 - isoindol ona among others. It also relates to a Pharmaceutical composition.These compounds are inhibitors of phosphodiesterase type 10a being useful in the treatment of schizophrenia, bipolar disorder, depression, Alzheimers diseaseSE REFIERE A COMPUESTOS HETEROCICLICOS DE FORMULA (I) DONDE X1 ES N O CR1 X2 ES N O CR2 X3 ES N O CR3 X4 ES N O CR4, EN DONDE R1 Y R4 SON CADA UNO H, HALOGENO, ALQUILO(C1-C4), ENTRE OTROS R2 Y R3 SON CADA UNO H, OH, ALCOXI(C1-C4)-ALQUILO(C1-C4), ENTRE OTROS A ES O, S, S(=O), S(=O)2, ENTRE OTROS Het ES FENILO, HETARILO MONOCICLICO O HETARILO BICICLICO R7, R8, R9 Y R10 SON CADA UNO H, HALOGENO, ALQUILO(C1-C4), FLUOROALCOXI(C1-C4), ENTRE OTROS. SON COMPUESTOS PREFERIDOS: 4-PIRIDIN-4-IL-2-(2-QUINOLIN-2-IL-ETIL)-1,2-DIHIDRO-PIRROLO[3,4-c]PIRIDIN-3-ONA 7-PIRIDIN-4-IL-2-(2-QUINOLIN-2-IL-ETIL)-2,3-DIHIDRO-PIRROLO[3,4-c]PIRIDIN-1-ONA 3,3-DIFLUORO-7-PIRIDIN-4-IL-2-(2-QUINOLIN-2-IL-ETIL)-2,3-DIHIDRO-ISOINDOL-1-ONA ENTRE OTROS. TAMBIEN SE REFIERE A UNA COMPOSICION FARMACEUTICA. DICHOS COMPUESTOS SON INHIBIDORES DE LA FOSFODIESTERASA TIPO 10A SIENDO UTILES EN EL TRATAMIENTO DE ESQUIZOFRENIA, TRASTORNO BIPOLAR, DEPRESION, ENFERMEDAD DE ALZHEIMER
