JPS6045180B

Compounds, which have antispasmodic effects, represented by the following formula (I) (I) wherein R1 and R2, which may be the same or different, each represents a hydrogen atom, an alkoxy group or, when taken together, R1 and R2 represent an alkylenedioxy group; R3 represents a hydrogen atom, an alkyl group or a cycloalkyl group; R4, R5 and R6, which may be the same or different, each represents a hydrogen atom, an alkoxy group, an alkyl group, a halogen atom, a hydroxyl group or, when two of R4, R5 and R6 are taken together, they represent an alkylenedioxy group; and A represents a straight or branched chain alkylene group having 2 to 10 carbon atoms or an alkylene group having 2 to 10 carbon atoms and interrupted with an oxygen atom forming an ether bond therein, and the therapeutically useful acid-addition salts thereof; and a process for producing the same.