ETHYLAMINE DERIVATIVES

Novel ethylamine derivatives represented by general formula (I) and pharmaceutically acceptable acid-addition salts thereof, wherein R1 represents hydrogen, hydroxy, lower alkoxy or halogeno; R2 represents C2-5 alkyl; R3 represents hydrogen, C2-5 alkyl, C2-5 alkylcarbonyl, C6-10 aryl or C7-11 aralkyl; and the ring A means a bicyclic compound consisting of at least one benzene ring and a saturated or unsaturated 5- or 6-membered ring optionally containing heteroatom(s), provided that R2 and R3 do not carry each two carbon atoms at the same time when the ring A is indole or 1,3-benzodioxole; and the ring A is a bicyclic compound other than indole or benzo¢b!thiophene and R2 is a C3-5 alkyl when R3 is hydrogen. Because of having catecholamine-potentiating effects and high selectivity for the CAE effect, these compounds are useful as psychotropic drugs, antidepressants, antiparkinson agents and antialzheimer agents.