Crystal structures of (12E)-12-(4-benzylidene)-7,7,16-trimethyl-3-(4-methylphenyl)-1-oxa-16-azatetracyclo[11.2.1.02,11.04,9]hexadeca-2(11),4(9)-dien-5-one and (12E)-12-(4-bromobenzylidene)-73-(4-bromophenyl)-,7,16-trimethyl-10-oxa-16-azatetracyclo[11.2.1.02,11.04,9]hexadeca-2(11),4(9)-dien-5-one

The title compounds, C32H35NO2, (I), and C30H29Br2NO2, (II), differ by the presence of a bromine atom instead of a methyl atom in the para position of two benzene rings of compound (II). The two compounds have a structural overlap r.m.s. deviation of 0.27 Å. The pyran and seven-membered cycloheptene rings in both structures adopt boat and boat-sofa conformations, respectively. Intra- and intermolecular C—H...O hydrogen bonds are responsible for the consolidation of the crystal packing of both molecules. In addition to this, weak C—H...π interactions are also observed. The intermolecular interactions were quantified and analysed using Hirshfeld surface analysis.