A compound represented by the following general formula (I): [wherein R 1 represents hydrogen atom or a C 1-6 alkyl group, A and B represent -(CH 2 ) 2 -, -(CH 2 ) 3 - or -(CH 2 ) 4 -, X represents -N(R 2 )-CO- (R 2 represents hydrogen atom or a C 1-6 alkyl group), -CO-N(R 3 )- (R 3 represents hydrogen atom or a C 1-6 alkyl group), -C(R 4 )=C(R 5 )- (R 4 and R 5 represent hydrogen atom or a C 1-6 alkyl group), or -N(R 6 )-SO 2 -(R 6 represents hydrogen atom or a C 1-6 alkyl group), and Ar represents an aryldiyl group or a heteroaryldiyl group], which has a retinoid action and is useful as an active ingredient of a medicament.