A compound represented by the formula (1): wherein R 1 represents a hydroxyl group, a dimethylphosphynoyloxy group, etc.； and R 2 and R 3 represent a methoxy group, etc., or a pharmaceutically acceptable salt thereof can reduce a score of telangiectasia around the meibomian gland orifices and a number of obstruction at the orifices, so that it is useful as a prophylactic and/or therapeutic agent for meibomian gland dysfunction.
