koxy having 1 to 4 carbon atoms or alkyl having 1 to 4 carbon atoms; Ar represents ##STR202## wherein R2 represents alkyl having 1 to 4 carbon atoms, R3 represents hydrogen, halogen, alkyl having 1 to 4 carbon atoms, alkoxy having 1 to 4 carbon atoms or dialkyl amino, n is an integer of 1 or 2; when n is 2, R3 may be the same or different; R4 and R5 represent hydrogen, substituted or non-substitut