PROBLEM TO BE SOLVED: To provide a compound having PDE2A selective inhibitory action, and a pharmaceutical composition comprising the same.SOLUTION: The present invention provides a compound represented by formula (I) or their pharmaceutically acceptable salt, or their solvate, and a pharmaceutical composition comprising them [m is an integer of 1 to 5 Y1 is N or C Y2 is C-R2a or N-R2b ring B is a benzene ring or the like Z is CR5aR5b or O R1 is a C1-6 alkyl group or the like R2a is a halogen atom, a C1-6 alkyl group or the like R2b is a C1-6 alkyl group or the like R3a and R3b each independently represent H, a C1-6 alkyl group or the like R4 independently represent a hydroxy group, a halogen atom or the like R5a and R5b in Z each independently represent H, a C1-6 alkyl group and the like].SELECTED DRAWING: NoneCOPYRIGHT: (C)2017,JPO&INPIT【課題】PDE2A選択的阻害作用を有する化合物、及びそれを含有してなる医薬組成物の提供。【解決手段】式(I)で示される化合物若しくはそれらの製薬学的に許容される塩、又はそれらの溶媒和物、及びこれらを含有してなる医薬組成物。[mは1~5の整数;Y1はN又はC;Y2はC-R2a又はN-R2b;環Bはベンゼン環等;ZはCR5aR5b又はO;R1はC1~6アルキル基等;R2aはハロゲン原子、C1~6アルキル基等;R2bはC1~6アルキル基等;R3a及びR3bは各々独立して、H、C1~6アルキル基等;R4は各々独立して、水酸基、ハロゲン原子等;ZにおけるR5a及びR5bは各々独立して、H、C1~6アルキル基等]【選択図】なし
