Abstract: The invention relates to novel dibenzo[1,2;5,6]cyclohepta pyridine or -pyrrole derivatives, dibenzo[2,3;6,7]oxepino pyridine or pyrrole derivatives, dibenzo[2,3;6,7]thiepino pyridine or pyrrole derivatives and dibenzo[b,f]pyrido or pyrrolo azepine derivatives of general formula: ##STR1## as well as the pharmaceutically acceptable salts and nitrogen oxides thereof, whereinR.sub.1, r.sub.2, r.sub.3 and R.sub.4 each represent hydrogen, hydroxy, halogen, an alkyl (1-6 C) group, an alkoxy or alkylthio group in which the alkyl group contains 1-6 C-atoms, or a trifluoromethyl group,R.sub.5 represents hydrogen, an alkyl group with 1-6 carbon atoms or an aralkyl group with 7-10 carbon atoms,M is the number 1 or 2,X represents oxygen, sulphur, the group ##STR2## OR THE GROUP --CH.sub.2 -- and R.sub.6 represents hydrogen or a lower alkyl group (1-4 C),having CNS-depressant activity and excellent antihistamine and antiserotonin activities.

Abstract: Compounds of formula I, ##STR1## wherein either R.sub.1 is hydroxy or alkoxy of 1 to 4 carbon atoms, and R.sub.2 is hydrogen, hydroxy or alkoxy of 1 to 4 carbon atoms,Or R.sub.1 and R.sub.2, together, are methylenedioxy,R.sub.3 is hydrogen or alkyl of 1 to 4 carbon atoms, andR.sub.4 is phenyl or phenyl substituted by 1, 2 or 3 substituents independently chosen from halogen, hydroxy, nitro or alkyl(C.sub.1-4) haloalkyl(C.sub.1-4), or alkoxy (C.sub.1-4),are useful as anti-arrhythmic agents.