title: Structure, photophysics, electrochemistry, DFT calculation, and in-vitro antioxidant activity of coumarin Schiff base complexes of Group 6 metal carbonyls.
abstract: N-[(2-Pyridyl)methyliden]-6-coumarin (L) is synthesized by the condensation of 6-aminocoumarin and pyridine-2-carboxaldehyde. Group-6 tetracarbonyl complexes, [M(CO)(4)(L)] (M=Cr, Mo, and W) are synthesized and characterized by mass spectrometry and NMR, FT-IR and UV-visible spectroscopy. X-ray crystal structure of [Cr(CO)(4)(L)] shows N(pyridine), N(imine) chelation to chromium(0). A supramolecular chain is formed by C-H⋯O and π⋯π interactions. The ligand and the complexes are fluorescent. Cyclic voltammetry of the complexes exhibit quasireversible M(I)/M(0) redox couple. The complexes exhibit potential antioxidant property both in cell free and in-vitro studies and highest activity is observed to [W(CO)(4)(L)]. Density functional theory (DFT) computation has been performed to correlate with the electronic configuration, composition of wave functions with the UV-visible spectra and redox properties.
authors.affiliation: Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata, India.
authors.forename: Papia
authors.initials: P
authors.lastname: Datta
authors.forename: Ambika Prasad
authors.initials: AP
authors.lastname: Mukhopadhyay
authors.forename: Prasenjit
authors.initials: P
authors.lastname: Manna
authors.forename: Edward R T
authors.initials: ER
authors.lastname: Tiekink
authors.forename: Parames Chandra
authors.initials: PC
authors.lastname: Sil
authors.forename: Chittaranjan
authors.initials: C
authors.lastname: Sinha
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry*; D003374:Coumarins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004563:Electrochemistry / Q000379:methods; D022781:Hepatocytes / Q000378:metabolism; D008024:Ligands; D051379:Mice; D012545:Schiff Bases / Q000737:chemistry
chemical_list: D000975:Antioxidants; D056831:Coordination Complexes; D003374:Coumarins; D008024:Ligands; D012545:Schiff Bases