Department of Chemistry, Payame Noor University, P.O. BOX 19395-4697 Tehran, Iran
In this work, the optimization calculations were carried out on quetiapine hemifumarat, 4, and its analogues, 1-5. These calculations were carried out using the B3LYP/6-31G(d) level of theory. The DFT calculations clarified a boat structure for dibenzothiazepine moiety of the molecule which piperazine moiety has a chair conformation. Thermal energies (E), enthalpies (H), and free energies (G) of quetiapine and its analogues, 1-5 were calculated at the B3LYP/6-31G(d) level. The chemical hardness (η), chemical potential (μ), dipole moment (D), electrophilicity (ω) and the maximum amount of electronic charge, ΔNmax, were determined. Some molecular properties for quantitative structure activity relationships (QSAR) were investigated.
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