[MORIMOTO, Toshiharu, KOSHIZAWA, Tomoaki, WATANABE, Gen, FUKUDA, Tomoaki, OHGIYA, Tadaaki, YAMASAKI, Nao, INOUE, Noriyuki, ARAKI, Takaaki, TSUKAGOSHI, Hitomi, HAGITA, Sumihiko] 6-29, Nishiki 3-chome, Naka-ku, Nagoya-shi, Aichi 4608625;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022;c/o KOWA COMPANY, LTD., Tokyo New Drug Research Laboratories, 2-17-43, Noguchi-cho, Higashimurayama-shi, Tokyo 1890022 Provided is a novel compound which has an effect of promoting insulin secretion from pancreatic β cells and is useful as a prophylactic and/or therapeutic agent for diseases associated with high blood sugar, such as diabetes. A compound represented by general formula (1), a salt thereof, or a solvate of the compound or the salt. (In the formula, ring A represents a C6-C10 aryl group or a five- to ten-membered heterocyclic group; Z represents O, N-R9, S(O)m, CH2 or C=O; each of R1, R2, R3 and R4 is independently absent or represents a hydrogen atom, a halogen atom, a C1-6 alkyl group, a hydroxyl group, a nitro group, a tetrazolyl group or the like; each of R5, R6 and R7 independently represents a hydrogen atom, a halogen atom, a cyano group or a carboxyl group; R8 represents a C1-6 alkyl group, a C6-10 aryl group or the like; each of R13 and R14 represents a hydrogen atom or a halogen atom; and R15 represents a hydrogen atom, a hydroxyl group or an oxo group.)