Publications internationales
Résumé: This review discusses recent progress in the most significant synthetic approachesinvolving transformations under the Mitsunobu reaction. The Mitsunobu reactionentails the "redox" condensation of an acidic pronucleophile ‘Nu-H’ and an electro-philic primary or secondary alcohol, facilitated by stoichiometric amounts of phos-phines and azodicarboxylate reagents. Widely utilized for dehydrative oxidation–reduction condensation, this reaction shows synthetic utility through its toleranceof a broad range of acidic pronucleophiles, including carboxylic acids, pro-imides,hydroxamates, phenols, thiols, fluorinated alcohols, oximes, thioamides, pyridiniumand imidazolium salts, pyrimidine bases, α-ketoesters, and trimethylmethane tricar-boxylate, thereby yielding a variety of functional and potentially biologically activecompounds. The purpose of this review is to focus on recent advances and applica-tions of Mitsunobu reaction chemistry, particularly from 2010 to 2024. In additionto discussing newer reagents that facilitate purification, we will describe contem-porary applications of this chemistry, especially concerning the synthesis of poten-tial biological compounds and their precursors. This focus review of the Mitsunobureaction summarizes its origins, the current understanding of its mechanism, andrecent improvements and applications. We aim for this work to serve as a usefulresource for scientists working in this research domain
Résumé: In this paper, we have attempted a theoretical calculation of some plant-isolated compounds as potential inhibitors of oxidative stress and Advanced Glycation Endproducts (AGEs). Herein, theoretical reactivity indices based on the CDFT theory were computed to explore the reactivity of five isolated products from Calophyllum flavoramulum. Global reactivity indices based on HOMO and LUMO energy such as electronic chemical potential, hardness, electrophilicity and the local reactivity descriptors Parr function, molecular electrostatic potentials(MEP), electrostatic potential (ESP) and thermodynamic parameters for the studied compounds are computed and discussed using DFT method and two functionals B3LYP and CAM-B3LYP with 6-31 G(d,p) basis set. The free radical scavenging activity mechanisms (HAT, SET-PT, and SPLET) of some of the isolated products with DPPH are also presented in this work. SET-PT mechanism of the antiradical activity is found to be thermodynamically favorable. Furthermore, a molecular docking study with RAGE receptor and AtGSTF2 enzyme was conducted, in which flavonoids 4 and 5 show a low binding affinity with −8.42 and −10.49 kcal/mol for RAGE, −8.67 and −9.00 kcal/mol for AtGSTF2. After the encouraging outcomes from the molecular docking study, the 4-AtGSTF2 and 5-RAGE complex were subjected to 200 ns molecular dynamics simulation using Desmond, where both studied systems exhibited remarkable stability throughout the 200 ns simulations. Also, the MM-GBSA method was measured by calculating the binding free energy using the individual energy components. Finally, the ADMET predictions were assessed to anticipate the behavior of a drug candidate within the human body.
Résumé: Seven components from the methanol extract of the aerial part of the endemic species Helianthemum confertum were isolated and identified for the first time. Investigating this species and its separated components chemical make-up and radical scavenging capacity, was the main goal. Using an online HPLC-ABTSc+ test, ORAC, and TEAC assays, the free radical scavenging capacity of the ethyl acetate extract was assessed. The fractionation of these extracts by CC, TLC, and reverse-phase HPLC was guided by the collected data, which was corroborated by TEAC and ORAC assays. Molecular docking studies, DFT at the B3LYP level, and an examination of the ADME/T predictions of all compounds helped to further clarify the phytochemicals' antioxidant potential. Isolation and identification of all components were confirmed through spectroscopy, which revealed a mixture (50–50%) of para-hydroxybenzoic acid 1 and methyl gallate 2, protocatechuic acid 3, astragalin 4, trans-tiliroside 5, cis-tiliroside 6, contaminated by trans-tiliroside and 3-oxo-a-ionol-b-D-glucopyranoside 7, as well as two new compounds for the genus Helianthemum (2 and 7). With a focus on compounds 1, 2, 3, and 4, the results clearly showed that the extract and the compounds tested from this species had a high antioxidant capacity. Within the xanthine oxidase enzyme's pocket, all of the components tested showed strong and stable binding. In light of these findings, the xanthine oxidase/methyl gallate 2 complex was simulated using the Desmond module of the Schrodinger suite molecular dynamics (MD) for 100 ns. Substantially stable receptor–ligand complexes were observed following 1 ns of MD simulation.
Résumé: An environmentally benign protocol for the synthesis of a novel series of imine derivatives containing 2-oxo-3H-benzoxazole scaffold was successfully developed. Thus benzoxazolinone-6-carbaldehyde (3) was carried out by the formylation of 3-methyl-2-oxo-3H-benzoxazole (1) using hexamethylenetetramine (HMTA) in polyphosphoric acid (PPA). The designed compounds were prepared by the treatment of compound (3) with primary amines in the presence of methanol as solvent, by using ultrasonic-assisted method under catalyst-free conditions and conventional heat in methanol at reflux in presence of catalytic amount of acetic acid, to afforded the pure desired 6-imino-2-oxo-3H-benzoxazoles (4a-4f) in appreciable yields; their purity was confirmed by melting point as well as thin layer chromatography (TLC). The chemical structures of the new synthesized compounds were elucidated on the basis of the FT-IR, 1 H and 13 C-NMR spectroscopic techniques.