PROBLEM TO BE SOLVED: To provide morphinan derivatives having opioid δ receptor agonist activity.SOLUTION: The present invention provides morphinan derivatives represented by general formula (I) in the figure, tautomers and stereoisomers of the compounds, or pharmaceutically acceptable salts or solvates thereof. In the formula (I), R1 represents hydrogen, C1-6 alkyl, aralkyl or the like R2 and R3 represent hydrogen, hydroxyl or the like R4, R5 and R6 represent hydrogen, C1-6 alkyl or the like, or R5 is combined with R4 or R6 to form a 4-7 membered ring together with the N atom linked to R5 and X represents O or CH2.COPYRIGHT: (C)2016,JPO&INPIT【課題】オピオイドδ受容体アゴニスト作用を有するモルヒナン誘導体の提供。【解決手段】下記一般式(I)で表されるモルヒナン誘導体、該化合物の互変異性体、立体異性体、若しくはその薬学的に許容される塩又はそれらの溶媒和物。式(I)中、R1は水素、C1-6アルキル、アラルキル他を表し、R2及びR3は、水素、ヒドロキシ他を表し、R4、R5及びR6は水素、C1-6アルキル他を表すか、或いはR5がR4又はR6と一緒になって、R5が結合するN原子と共に4~7員環を形成しても良く、XはO又はCH2を表す。【選択図】なし
