S. Russi et al., 4,5,6,9-tetramethoxy-11-phenyl-10-oxa-11-azatri-cyclo[7.2.2.0(2,7)]trideca-2(7),3,5,12-tetraen-8-one, ACT CRYST E, 57, 2001, pp. O444-O446
The crystal structure of the adduct, C21H21NO2, of tetramethylpurpurogallin
with nitrosobenzene is reported. The compound exhibits a [3.2.2] bicyclic
system corresponding to two seven-membered rings and one six-membered ring
in distorted chair, boat and twist-boat conformations, respectively. One in
tramolecular and two intermolecular hydrogen bonds direct the packing and s
tabilize the molecule.