The invention relates to a DGAT inhibitor of formula (I): including any stereochemically isomeric form thereof, wherein A represents CH or N； the dotted line represents an optional bond in case A represents a carbon atom； X represents &mdash；C(&boxH；O)&mdash；； &mdash；O&mdash；C(&boxH；O)&mdash；； C(&boxH；O)&mdash；C(&boxH；O)&mdash；； &mdash；NRx&mdash；C(&boxH；O)&mdash；； &mdash；Z1&mdash；C(O)&mdash；； &mdash；Z1&mdash；NRx&mdash；C(&boxH；O)&mdash；； &mdash；C(&boxH；O)&mdash；Z1&mdash；； &mdash；NRx&mdash；C(&boxH；O)&mdash；Z1&mdash；； &mdash；S(&boxH；O)p-； &mdash；C(&boxH；S)&mdash；； &mdash；NRx&mdash；C(&boxH；S)&mdash；； &mdash；Z1&mdash；C(&boxH；S)&mdash；； &mdash；Z1&mdash；NRx&mdash；C(&boxH；S)&mdash；； &mdash；C(&boxH；S)&mdash；Z1-； &mdash；NRx&mdash；C(&boxH；S)&mdash；Z&mdash；； Y represents NRx&mdash；C(=0)-Z2&mdash；； &mdash；NRx&mdash；C(=0)-Z2&mdash；NRy&mdash；； &mdash；NRx&mdash；C(=0)-Z2&mdash；NRy&mdash；C(=0)-； &mdash；NRx&mdash；C(=0)-Z2&mdash；NRy&mdash；C(=0)-O&mdash；； &mdash；NRx&mdash；C(=0)-Z2-0-； &mdash；NRx&mdash；C(=0)-Z2-0-C(=0)-； &mdash；NRx&mdash；C(=0)-Z2&mdash；C(=0)-； &mdash；NRx&mdash；C(=0)-Z2&mdash；C(=0)-； &mdash；NRx&mdash；C(=0)-0-Z2&mdash；C(=0)-； &mdash；NRx&mdash；C(=0)-0-Z2&mdash；C(=0)-0-； &mdash；NRx&mdash；C(&boxH；O)&mdash；O&mdash；Z2&mdash；O&mdash；C(&boxH；O)&mdash；； &mdash；NRx&mdash；C(&boxH；O)&mdash；Z2&mdash；C(&boxH；O)&mdash；NRy&mdash；； &mdash；NRx&mdash；C(&boxH；O)&mdash；Z2&mdash；NRy&mdash；C(=0)-NRy&mdash；； &mdash；C(&boxH；O)&mdash；Z2&mdash；； &mdash；C(&boxH；O)&mdash；Z2&mdash；O&mdash；； &mdash；C(=0)-NRx&mdash；Z2&mdash；； &mdash；C(=0)-NRx&mdash；Z2-0-； &mdash；C(=0)-NRx&mdash；Z2&mdash；C(=0)-0-； &mdash；C(=0)-NRx&mdash；Z2-0-C(=0)-； &mdash；C(=0)-NRx&mdash；Z2&mdash；NRy&mdash；； &mdash；C(=0)-NRx&mdash；Z2&mdash；NRy&mdash；C(=0)-； &mdash；C(=0)-NRx&mdash；Z2&mdash；NRy&mdash；C(=0)-0-； R1 represents C1-12alkyl optionally substituted with cyano, C1-4alkyloxy, C1-4alkyl-oxyC1-4alkyloxy, C3-6Cycloalkyl or aryl； C2-6alkenyl； C2-6alkynyl； C3-6cycloalkyl； adamantanyl； aryl1； aryl1C1-6alkyl； Het1； or Het1C1-6alkyl； provi
