The present invention provides a compound represented by formula (I), a pharmaceutically acceptable salt thereof or a solvate thereof. (In the formula, each of A and Z independently represents CO, SO or SO 2 ； each of X and Y independently represents S or O； each of R 1 -R 4 independently represents hydrogen, alkyl, alkenyl, alkynyl or halo； each R 5 independently represents alkyl, alkenyl, alkynyl or halo； and n represents an integer of 0-4.) This compound is capable of specifically binding to an AMPA receptor, and shows extremely high brain uptake.
