Density functional theory study of semiquinone radical anions of polychlorinated biphenyls in the syn- and anti-like conformation.
J Phys Chem A
; 116(6): 1586-95, 2012 Feb 16.
Article
em En
| MEDLINE
| ID: mdl-22257259
Polychlorinated biphenyls (PCBs) can be metabolized to reactive metabolites, such as PCB semiquinone radical anions (SQ(â¢-)), whose structure and role in PCB-induced toxicity are difficult to investigate due to their relative instability. The unrestricted UB3LYP/6-311G** method was used to investigate several molecular descriptors of the syn- and anti-like conformation of SQs(â¢-). The bond lengths and angles of the quinone moiety of the SQs(â¢-) were in between the values reported for PCB quinones and hydroquinones, which is consistent with the distribution of the α highest occupied molecular orbital (α-HOMO). The dihedral angles between the two ring systems increased in the presence of ortho chlorine substituents and were smaller compared to the corresponding PCB quinones. The ground-state energies indicate that the anti-like conformation of the SQs(â¢-) is more favorable than the syn-like conformation. Molecular descriptor used for modeling of quantitative structure-activity relationships displayed some dependence on the conformation. These findings suggest that SQs(â¢-) in both the syn- and antilike conformation may interact differently with target molecules, which may have implications for the toxicity of PCBs.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Teoria Quântica
/
Benzoquinonas
/
Bifenilos Policlorados
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article