Structural relationships in the solid state of the anti-chagas agent
(E)-phenylethenylbenzofuroxan
MOLECULAR DIVERSITY, 14 (4):
643-652 (2010)DOI: 10.1007/s11030-009-9202-4
Abstract
The crystal structure and the vibrational spectrum of a potential drug
for Chagas's disease treatment, the (E)-isomer of
phenylethenylbenzofuroxan 1
(5(6)(E)-(2-phenylethenyl)benzo1,2-c1,2,5-oxadiazole N-oxide),
are reported. In order to provide insights into structural
relationships, quantum mechanical calculations were employed starting
from crystal structure. These results have given theoretical support to
state interesting structural features, such as the effect of some
intermolecular contacts on the molecule conformation and the electronic
delocalization decreasing through atoms of the benzofuroxan moiety.
Furthermore, the MOGUL comparative analysis in the Cambridge Structural
Database provided additional evidences on these structural behaviors of
compound 1. Intermolecular contacts interfere on the intramolecular
geometry, as, for instance, on the phenyl group orientation, which is
twisted by 12.32(6)A degrees from the ethenylbenzofuroxan plane. The
experimental Raman spectrum of compound 1 presents unexpected frequency
shift and also anomalous Raman activities. At last, the molecule
skeleton deformation and the characteristic vibrational modes were
correlated by matching the experimental Raman spectrum to the calculated
one.