| 摘要 |
<p>A compound of formula (I) wherein R?1 and R2¿ independently represent H or an optionally substituted hydrocarbon group; R3 represents an optionally substituted hydrocarbon group: R4 represents H or a hydrocarbon group; ring A represents a substituted benzene ring; X represents a C¿2-4? alkylene group etc.; and Y represents a bond or a lower alkylene group, or salts thereof is useful as prophylactic or therapeutic agents of diseases related with melatonin activity.</p> |
