DIAMINOCYCLOBUTENE-3,4-DIONE DERIVATIVES, THEIR PREPARATION AND USE

摘要

The present invention discloses compounds having formula (1) or a pharmaceutically acceptable salt thereof, wherein X represents (2), Y represents O or S. The meaning of R', R'', R''', R?2, R3, R4, R5, and R6¿ are specified in the application. The compounds are useful as chloride channel blockers.