The present invention is to create a compound that selectively activates glucokinase in the liver, and in particular, to provide an agent for treating and preventing diabetes and impaired glucose tolerance, wherein the agent has a low hypoglycemia risk. A compound represented by the formula (1) as shown below, or a salt thereof, or a solvate of the compound or the salt:wherein, in the following formula (1), ring A represents a thiazolyl group, a pyridyl group, a pyrazyl group, or a pyrazolyl group; L represents —(CO)—, —(CS)—, or —SO2—; and R1 represents a C1-6 alkyl group, a hydroxy C1-6 alkyl group, a C1-6 alkoxy group, an amino group, a C1-6 alkylamino group, a hydroxyamino group, an N—C1-6 alkylcarbamoyl group, or a group represented by the formula (2) as shown below, wherein R3 represents a C1-6 alkyl group; and R2 represents a hydrogen atom, a halogen atom, a C1-6 alkyl group, a C1-6 alkoxy group, or a carboxyl group. The formulas are shown below: