The present invention relates to provision of a novel compound that has an activity of promoting insulin secretion from pancreatic β cells and thus is useful as a prophylaxis and/or therapeutic agent for diseases caused by hyperglycemia such as diabetes mellitus, andthe compound represented by the following formula (1): wherein one of A and B represents a nitrogen atom and the other represents a nitrogen atom or CR10, X represents an oxygen atom, a sulfur atom or —(CH2)n-N(R12)—, Y represents an oxygen atom, a sulfur atom or —N(R13)—, and R1 to R9 each represent a hydrogen atom or another substituent, or a salt thereof, or a solvate of the compound or the salt.