Heterocyclic compounds useful as alpha 2-adrenoceptor antagonists

摘要

A compound of formula (I): <IMAGE> (I) or a pharmaceutically acceptable salt thereof, wherein: R1 and R2 may each represent hydrogen or alkyl providing that at least one of R1 or R2 represents alkyl; R3 and R4 each represent hydrogen or R3 and R4 together represent a bond; n represents an integer 1 or 2; and m represents an integer 1 or 2; a composition containing such a compound and the method of using such compounds and compositions in medicine.