INDANE DERIVATIVE

PROBLEM TO BE SOLVED: To obtain a new indane derivative having a bradycardiac activity and useful for the treatment of heart failure of mammalian animals including human. SOLUTION: This indane derivative is a compound of formula I [R1 is H, a halogen, a 1-6C alkyl or the like; R2, R3 are each a 1-6C alkyl or the like; R4 is OH, a 1-6C alkylcarbonyloxy or forms epoxy group together with R5; R5 is H or forms the epoxy group together with R4; R6 is H, OH, a 1-6C alkoxy or the like; (n) is 0-4; X is C=O, CH2, SO2 or the like; Y is NR17 (R17 is H, a 1-4C alkyl, phenyl or the like) or C=O; Z does not exist when Y is NR17, and is NR18 (R18 is the same as NR17) when Y is C=O; W is an aromatic group, a lactam ring or the like]. For example, 6-(4'-methoxybenzylcarboxyamide)-3, 3-dimethyl-1-indene. The compound of the formula I is obtained e.g. by reacting a compound of formula II with acid chloride of formula III in the presence of a base.