Abstract: The invention concerns:Novel dibenz/b,e/oxepin and dibenz/b,e/thiepin compounds having the general formula: ##STR1## wherein X is O or S,R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are the same or different and are each selected from the group consisting of hydrogen, lower alkyl, lower alkenyl, lower alkynyl, lower cycloalkyl, lower alkoxy, lower alkylthio, lower alkylsulphinyl, lower alkylsulponyl, halogen, trifluoromethyl, trifluoromethylthio, lower dialkylsulphonamido, nitro, hydroxy, cyano, carbamyl, carboxy, lower alkoxycarbonyl, amino, N-lower alkylamino, N,N-diloweralkylamino, lower acylamido, lower alkanesulfonamido and lower acyl and, when on adjacent carbon atoms at the positions 2 and 3 and/or 8 and 9, two of the substituents R.sup.1 and R.sup.2 or R.sup.3 and R.sup.4 taken together may form a methylenedioxy group;R.sup.5 and R.sup.