title: FT-IR spectroscopy, intra-molecular C-H⋯O interactions, HOMO, LUMO, MESP analysis and biological activity of two natural products, triclisine and rufescine: DFT and QTAIM approaches.
abstract: The present study deals with two natural products, triclisine and rufescine which are extracted from the Amazonian wines but ubiquitous in nature. The quantum chemical density functional method at B3PW91/6-311+G(d,p) level is used to obtain the equilibrium geometries of these molecules. The quantum theory of atoms-in-molecule approach is employed to study various intra-molecular C-H⋯O interactions within these molecules. We have also performed vibrational analyses of triclisine and rufescine at their equilibrium geometries and presented the complete assignments of the significant vibrational modes. The calculated vibrational frequencies are shown to be in perfect agreement with the experimentally observed FTIR spectra of molecules under study. In addition, the electronic properties of these molecules are also discussed with the help of HOMO-LUMO and MESP surfaces and a number of electronic as well as thermodynamic parameters are calculated which are closely related to their chemical reactivity and reaction paths. The biological activities of both molecules have also been predicted which highlight their pharmacological importance.
authors.affiliation: Department of Physics, University of Lucknow, Lucknow, Uttar Pradesh 226007, India.
authors.forename: Ambrish Kumar
authors.initials: AK
authors.lastname: Srivastava
authors.affiliation: Department of Physics, Govt. D.P.G. College, Dantewada, Chhattisgarh 494449, India.
authors.forename: Anoop Kumar
authors.initials: AK
authors.lastname: Pandey
authors.affiliation: Department of Chemistry, University of Lucknow, Lucknow, Uttar Pradesh 226007, India.
authors.forename: Sudha
authors.initials: S
authors.lastname: Jain
authors.affiliation: Department of Physics, University of Lucknow, Lucknow, Uttar Pradesh 226007, India. Electronic address: neerajmisra11@gmail.com.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Misra
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology; D001372:Aza Compounds / Q000737:chemistry* / Q000494:pharmacology; D001688:Biological Products / Q000737:chemistry* / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D005449:Fluorenes / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D029583:Menispermaceae / Q000737:chemistry*; D008954:Models, Biological; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000970:Antineoplastic Agents; D001372:Aza Compounds; D001688:Biological Products; D004791:Enzyme Inhibitors; D005449:Fluorenes; C007738:fluoranthene
keywords: DFT; FT-IR; Natural products; QTAIM; Rufescine; Triclisine