Disclosed are compounds of the following formula and their pharmaceutically-acceptable salts, which have an effect of glucokinase activation and are useful in the field of medicines for treatment for diabetes, obesity, etc. (wherein ring A represents a pyrazolyl group optionally having a lower alkyl group, etc.； ring B represents a heteroaryl group； R represents a lower alkyl group, etc.； R 1 represents a group of a formula: (wherein R 11 and R 12 each independently represent a hydrogen atom, etc.； m indicates an integer of from 2 to 6), etc.； R 2 represents a lower alkyl group, etc.； r indicates an integer of from 0 to 3； k indicates an integer of from 0 to 4).
