Disclosed is a compound which is useful as an 11β-hydroxysteroid dehydrogenase type 1 inhibitor.A compound represented by the formula: its pharmaceutically acceptable salt, or a solvate thereof, wherein R1 is optionally substituted cycloalkyl, optionally substituted cycloalkylalkyl, optionally substituted heterocycle or optionally substituted heterocyclealkyl, X is —O—, —NR3—, —NR3C(═O)— or —NR3S(═O)2—, R2 is optionally substituted aryl, optionally substituted arylalkyl, optionally substituted heteroaryl or optionally substituted heteroarylalkyl, R3 is hydrogen or optionally substituted alkyl.