Disclosed is a compound useful as a type I 11βhydroxysteroid dehydrogenase inhibitor.A compound represented by the formula: a pharmaceutically acceptable salt or solvate thereof, wherein R1 is optionally substituted alkyl or the like, one of R2 and R4 is a group of formula: —Y—R5, wherein Y is —O— or the like, R5 is substituted alkyl (the substituent is optionally substituted cycloalkyl or the like), optionally substituted branched alkyl or the like, the other of R2 and R4 is hydrogen or optionally substituted alkyl, R3 is a group of formula: —C(═O)—Z—R6, wherein Z is —NR7— or —NR7—W—, R6 is optionally substituted cycloalkyl or the like, R7 is hydrogen or optionally substituted alkyl, W is optionally substituted alkylene, X is ═N— or the like, with the proviso that compounds wherein R2 is 2-(morphorino)ethoxy, R3 is N-(1-adamantyl)carbamoyl and R1 is benzyl are excluded.