Interaction of a ligand with DNA is often the basis of drug action of many molecules. Flavones are important in this regard as their structural features confer them the ability to bind to DNA. 2-(4-Nitrophenyl)-4H-chromen-4-one (4NCO) is an important biologically active synthetic flavone derivative. We are therefore interested in studying its interaction with DNA. Absorption spectroscopy studies included standard and reverse titration, effect of ionic strength on titration, determination of stoichiometry of binding and thermal denaturation. Spectrofluorimetry techniques included fluorimetric titration, quenching studies and fluorescence displacement assay. Assessment of relative viscosity and estimation of thermodynamic parameters from CD spectral studies were also undertaken. Furthermore, molecular docking analyses were also done with different short DNA sequences. The fluorescent flavone 4NCO reversibly interacted with DNA through partial intercalation as well as minor-groove binding. The binding constant and the number of binding sites were of the order 10(4) M-1 and 1 respectively. The binding stoichiometry with DNA was found to be 1:1. The nature of the interaction of 4NCO with DNA was hydrophobic in nature and the process of binding was spontaneous, endothermic and entropy driven. The flavone also showed a preference for binding to GC rich sequences. The study presents a profile for structural and thermodynamic parameters, for the binding of 4NCO with DNA. DNA is an important target for ligands that are effective against cell proliferative disorders. In this regard, the molecule 4NCO is important since it can exert its biological activity through its DNA binding ability and can be a potential drug candidate. (C) 2018 Elsevier B.V. All rights reserved.

A highly efficient environment-friendly Hantzsch 1,4-dihydropyridine synthesis under visible light in aqueous ethanol has been achieved in excellent yield via a one-pot three component reaction of various types of aliphatic and aromatic aldehydes with ethyl acetoacetate and ammonium hydroxide solution.

AbstractThe one‐pot three component reaction of ethyl acetoacetate, aldehydes and ammonia proceeds in aqueous ethanol under visible light to furnish 1,4‐dihydropyridines.

A highly efficient methodology for the synthesis of 3-methyl-4-arylmethylene-isoxazole-5(4H)-ones has been developed by visible light induced multicomponent reaction of aromatic aldehydes, ethyl acetoacetate, hydroxylamine hydrochloride, and sodium acetate in aqueous ethanol sans any phase transfer catalyst or promoter.

ChemInformVolume 43, Issue 16 Heterocyclic Compounds ChemInform Abstract: A New Synthesis of Flavones and Pyranoflavone by Intramolecular Photochemical Wittig Reaction in Water. Jhantu Das, Jhantu Das Dep. Chem., Jadavpur Univ., Kolkata 700 032, IndiaSearch for more papers by this authorSomnath Ghosh, Somnath Ghosh Dep. Chem., Jadavpur Univ., Kolkata 700 032, IndiaSearch for more papers by this author Jhantu Das, Jhantu Das Dep. Chem., Jadavpur Univ., Kolkata 700 032, IndiaSearch for more papers by this authorSomnath Ghosh, Somnath Ghosh Dep. Chem., Jadavpur Univ., Kolkata 700 032, IndiaSearch for more papers by this author First published: 22 March 2012 https://doi.org/10.1002/chin.201216141Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume43, Issue16April 17, 2012 RelatedInformation

A visible light induced rapid one pot intermolecular Sonogashira coupling and 5-endo-dig cyclization in water of ortho-halophenols and terminal alkynes catalyzed by [Pd] have been developed to furnish 2-aryl/alkyl benzofurans in good yields sans Ru or Ir complexes or any other additives.

A new synthetic approach toward the synthesis of flavones and pyranoflavone has been developed by light induced intramolecular photochemical Wittig reaction in water onto aryloxycarbonyl groups and suitably substituted phosphonium bromides sans any phase transfer catalyst or promoter.

The synthesis of 2-aryl/alkylbenzofurans has been achieved in high yields under photochemical conditions from readily accessible and suitably substituted phosphonium bromides by an intramolecular photochemical Wittig reaction onto aryloxycarbonyl groups.

A highly efficient environment-friendly photochemical methodology has been developed for the condensation of Meldrum’s acid with aromatic aldehydes in water–ethanol solution sans any catalyst, support or promoter.

In general, the intramolecular Wittig reaction of phosphonium salts (I) gives better yields under photochemical conditions than under microwave irradiation.

A new procedure for benzoylation of aromatic and aliphatic amines has been developed in neat phase without use of any solvent or alkali.