title: FT-IR and FT-Raman spectra, molecular structure and first-order molecular hyperpolarizabilities of a potential antihistaminic drug, cyproheptadine HCl.
abstract: Cyproheptadine hydrochloride (CYP HCl) {4-(5H-dibenzo[a,d]-cyclohepten-5-ylidene)-1-methylpiperidine hydrochloride} is a first-generation antihistamine with additional anticholinergic, antiserotonergic, and local-anesthetic properties. The geometry optimization, Mulliken atomic charges and wavenumber and intensity of the vibrational bands of all of the possible modes of CYP HCl have been calculated using ab initio Hartree-Fock (HF) and density functional theory (DFT) employing the B3LYP functional with the 6-311G(d,p) basis set. We have compared the calculated IR and Raman wavenumbers with experimental data. Quantum-chemical calculations of the geometrical structure, energies, and molecular electrostatic potential and NBO analysis of CYP HCl have been performed using the B3LYP/6-311G(d,p) method. The electric dipole moment (μ), static polarizability (α) and the first hyperpolarizability (β) values of the title compound have been computed using HF and DFT methods. The study reveals that the antihistaminic pharmacological property of CYP HCl has a large β value and, hence, may in general have potential applications in the development of non-linear optical materials. The experimental and calculated results for CYP HCl have also been compared with those for mianserin HCl.
authors.affiliation: University of Kocaeli, Faculty of Science, Dept. of Physics, Kocaeli, Turkey. Electronic address: seda.sagdinc@gmail.com.
authors.forename: Seda G
authors.initials: SG
authors.lastname: Sagdinc
authors.affiliation: University of Kocaeli, Faculty of Science, Dept. of Physics, Kocaeli, Turkey.
authors.forename: Dilek
authors.initials: D
authors.lastname: Erdas
authors.affiliation: University of Kocaeli, Faculty of Science, Dept. of Physics, Kocaeli, Turkey.
authors.forename: Ilknur
authors.initials: I
authors.lastname: Gunduz
authors.affiliation: University of Kocaeli, Faculty of Science, Dept. of Physics, Kocaeli, Turkey.
authors.forename: Ayse Erbay
authors.initials: AE
authors.lastname: Sahinturk
mesh_terms: D003533:Cyproheptadine / Q000737:chemistry*; D005765:Gastrointestinal Agents / Q000737:chemistry*; D006634:Histamine H1 Antagonists / Q000737:chemistry*; D008958:Models, Molecular; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D005765:Gastrointestinal Agents; D006634:Histamine H1 Antagonists; D003533:Cyproheptadine
keywords: Cyproheptadine HCl; DFT; HF; Hyperpolarizability; NBO; Vibrational studies