Synthesis, characterisation, estimation of ground-and excited-state dipole moments using solvatochromic shift and theoretical studies of new iminocoumarin derivatives

The study on the fluorescence and UV–Vis absorption of some iminocoumarins at ambient temperature in several solvents showed a bathochromic shift with the increase of the solvent polarity. The use of the solvathochromic method allowed us to determine the dipole moment in both ground and excited states. The studied molecules exhibit much higher dipole moments in the excited state than in the ground state, which can be due to the redistribution of π-electron densities in the excited state making molecules more polar with higher dipole moments. Furthermore, HOMO–LUMO gap were also estimated theoretically using B3LYP/6–311 + G (d,p) level of theory; the low energy gap indicated the eventual charge transfer interaction occurring in the molecules, and responsible for their light emitting properties.publishe

Proposal for an ecofriendly and economic strategy for efficient radioiodination of coumarin derivatives

Combination of the calculation of reactivity descriptors and the cold iodine test for some coumarin derivatives was used in order to optimize the radioiodination reaction. The strongly nucleophilic predicted coumarins were subjected to the action of cold iodine. With two coumarins substituted at 3 by the 2-hydroxybenzoyl group, iodination did not occur but a product of intramolecular heterocyclization was obtained. This strategy is useful for economic and environmentally friendly radioiodination.publishe

Green synthesis, characterization, structure, biological activity, theoretical calculations and drug-likeness analysis of coumarins

Condensation of salicylaldehydes and 2-hydroxynaphthaldehyde with various β−dicarbonyl derivatives 2a-c, in the presence of KF-Al2O3, leads to the synthesis of a series of coumarins 3-8 and benzo[f]coumarins 10 respectively by a solvent free reaction under microwave irradiation. The catalyst is recovered by a simple filtration and reused in subsequent reactions. The structure of all synthesized compounds has been established by using analytical techniques such as IR, 1H and 13C NMR spectroscopic spectra and elemental analysis. Most of the coumarins exhibited significant antibacterial activity against S. aureus Gram-positive bacteria compared to Cefotaxime as positive control. The compounds 4a and 7a demonstrated moderate antimicrobial activity against compound 8a is extremely sensitive.. In addition, the compounds showed moderate to good antiradical (DPPH) activity. Theoretical calculations let us to confirm the reaction mechanism. Parameters drug-likeness and physicochemical properties including pharmacokinetic analysis of the synthesized compounds was performed using DruliTo program.publishe

Recyclable Keggin Heteropolyacids as an Environmentally Benign Catalyst for the Synthesis of New 2-Benzoylamino-N-phenyl-benzamide Derivatives under Microwave Irradiations at Solvent-Free Conditions and the Evaluation of Biological Activity

2-Benzoylamino-N-phenyl-benzamide derivatives (5a–h) were prepared from 2-phenyl-3,1-(4H)-benzoxazin-4-one 3 and substituted anilines 4a–h in the presence of a Keggin-type heteropolyacids series (H3PW12O40·13H2O; H4SiW12O40·13H2O; H4SiMo12O40·13H2O; and H3PMo12O40·13H2O) as catalysts without solvent and under microwave irradiation. We found that the use of H3PW12O40·13H2O acid coupled to microwave irradiation allowed obtaining a high-yielding reaction with a short time. The compound structures were established by 1H-NMR and 13C-NMR. The antibacterial and antifungal activities of the synthesized compounds exhibited an inhibition of the growth of bacteria and fungi

Transition-metal complexes of N,N′-di(4-bromophenyl)-4-hydroxycoumarin-3-carboximidamide: synthesis, characterization, biological activities, ADMET and drug-likeness analysis

International audienc

Synthesis, characterization, theoretical studies, ADMET and drug-Likeness analysis: Electrochemical and biological activities of metal complexes of 3-(2-hydroxybenzoyl)-2H-chromen-2-one

International audienc