| abstract |
This invention provides the compounds of formula (I): or a pharmaceutically acceptable ester of such compound, or a pharmaceutically acceptable salt thereof, wherein R1 and R2 independently represent a hydrogen atom or the like; R3 represents a hydrogen atom, or the like; R4 represents a hydrogen atom or the like; (formula II) represents one of the following or the like; R5 represents an aryl group having from 6 to 10 ring atoms or the like; X represents an oxygen atom, or the like; Y represents an oxgen atom or the like and n represents an integer 0, 1 or 2. These compounds have ORL1-receptor antagonist activity; and therefore, are useful to treat diseases or conditions such as pain, various CNS diseases etc. |