TRICYCLIC SPIROPIPERIDINES

摘要

Compounds of general structural formula (I) or a pharmaceutically acceptable salt, hydrate or crystal form thereof, wherein X is O or CH2, R<1> is H if R<2> is not H or if R<2> is H then R<1> is (a), (b), (c) or (d); R<2> is -H if R<1> is not H or if R<1> is H then R<2> is (a), (b), (c) or (d); and R<3> is (e) or (f), are Class III antiarrhythmic agents.