| abstract |
The invention provides a compound of formula (I): (see formula (I)) in which R1 and R2 independently represent a hydrogen atom or the like; X represents a covalent bond or the like; A represents a heterocyclic or carbocyclic, bicyclic, aromatic, saturated or partially unsaturated group having 8 to 12 ring atoms, or the like; B represents a phenyl group or a heteroaryl group having 5 to 6 ring atoms or the like; These compounds are useful for the treatment of pathological conditions caused by the overactivation of the NMDA NR2B receptor such as pain, or the like in mammals, this invention also provides a pharmaceutical composition comprising the above compound. |