SULPHONAMIDE.

摘要

The invention concerns sulphonamides of general formula (I) and their pharmaceutically acceptable acid addition salts. In formula (I), R represents hydrogen or lower alkyl, R1 and R2 which may be the same or different each represents hydrogen, lower alkyl, lower alkoxy or halogen, R3 and R4 which may be the same or different each represents lower alkyl, halo(lower)alkyl or aryl, A represents a lower alkylene group having 1 to 3 carbon atoms in the chain between the two N atoms and X represents O, S or NR5 (where R5 is hydrogen or lower alkyl). The compounds possess alpha 2-adrenoceptor antagonistic activity in warm blooded animals.