[Problem]To provide a GPR40 activating agent having, as an active ingredient, a novel compound having a GPR40 agonist action, a salt of the compound, a solvate of the salt or the compound, or the like, particularly, an insulin secretagogue and a prophylactic and/or therapeutic agent against diabetes, obesity, or other diseases.[Means of Solving the Problem]A compound of Formula (I): (where p is 0 to 4; j is 0 to 3; k is 0 to 2; a ring A is a specific cyclic group; a ring B is a benzene ring, a pyridine ring, or a pyrimidine ring; X is —CH2—, O, —S(O)i— (i is 0 to 2), or —NR7—; R1 to R6 are specific groups), a salt of the compound, or a solvate of the salt or the compound.