http://depot.umc.edu.dz/handle/123456789/7649 Thu, 22 Oct 2026 11:23:23 GMT 2026-10-22T11:23:23Z http://depot.umc.edu.dz/handle/123456789/14862 Contribution à l’étude photochimique et à l’activité biologique de l’espèce hédysarum pallidum desf. et l’espèce LINAIRE PELISSERIANA. Dob ép. Douaa, Amina; Boumaza, Ouahiba This work is devoted to the phytochemical and biological study of two Algerian species: Hedysarum pallidum Desf. and Linaria pelisseriana that have not been previously subjected to any phytochemical study. The extraction of both species followed by chromatographic separation (CC, CCM) leads the isolation of 20 products. UHPLC-MS-DAD analysis identifies 28 products in the n-BUOH phase of Hedysarum pallidum. The GC-MS analysis of the two chloroform phases of the two species concede to identify 13 and 14 products of Hedysarum pallidum and Linaria pelisseriana respectively with structures identifies by comparison with literature data. Regarding biological activity, the n-BuOH extract presents the most satisfactory results. Seven in vitro tests were carried out to determine the antioxidant power (DPPH, ABTS, CUPRAC, reducing power, metal chelating effect, alkaline superoxide and phenanthroline); they have shown that it has very strong antioxidant power. In addition, the α-glucosidase inhibition test showed that the n-BuOH extract as well as the CHCl3 extract have interesting antidiabetic activity. For the inhibitory activity of acetylcholinesterase and buturylcholinesterase, the two species present a weak effect compared to standards. Sat, 14 Sep 2024 00:00:00 GMT http://depot.umc.edu.dz/handle/123456789/14862 2024-09-14T00:00:00Z http://depot.umc.edu.dz/handle/123456789/14861 Nouvelles synthèses d’hétérocycles Azotés et Oxygénés, évaluation biologique et étude théorique Zine, Yasmine; Boulcina, Raouf The objective of the work presented in this thesis is to develop new approaches to access a variety of nitrogen- and oxygen-containing polyheterocyclic compounds, as well as to evaluate their biological activity and conduct theoretical studies using DFT and molecular docking. The first chapter of the thesis is structured into three parts. In the first part of the first chapter, we investigated the effect of two new catalysts, Pyridinium-p-toluenesulfonate and triethylamine, for synthesizing derivatives of 2-amino-4-(aryl)-7-methyl-5-oxo-4H,5Hpyrano[4,3-b]pyran-3-carbonitrile, achieving high yields in reduced time. The structures of the compounds were confirmed by RMN and HRMS. The antibacterial tests on the synthesized compounds showed promising results. However, the tests for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition, as well as the evaluation of antioxidant activity, yielded limited performances. A DFT study was conducted on three representative molecules, and molecular docking assessed the antibacterial activity of the most promising compound. In the second part of the first chapter, we investigated a selective multi-component transformation of salicylaldehydes, 4-hydroxy-6-methyl-2H-pyran-2-one, and malononitrile in the presence of 10 mol% of PPTS. This reaction led to the formation of 2,4-diamino-5-[4- hydroxy-6-methyl-2-oxo-2H-pyran-3-yl]-5H-chromeno[2,3-b]pyridine-3-carbonitrile with excellent yields. The synthesized molecules showed promising potential in terms of biological activity. In the third part of the first chapter, we investigated the synthesis of several derivatives of tacrine successfully, with satisfactory yields. Spectroscopic analyses by RMN 1H and 13C confirmed the structures of the synthesized compounds, revealing characteristics consistent with expectations. In the second chapter, we developed a novel, simple, and effective method using DMAP as a catalyst without solvent to synthesize derivatives of 5-arylidene-thiazolidine-2,4-dione, obtained with excellent yields via Knoevenagel reaction. The compounds were characterized by RMN spectroscopy, and their physical properties were determined. Evaluation of antioxidant activity revealed the impact of substituents on their biological activity, with some compounds showing promising antioxidant activity. Computational simulations corroborated these observations. Additionally, we explored the potential of molecular docking for studying inhibition of PIM-1 kinase. In the third chapter, we investigated the synthesis of 4-arylmethylene-3-methylisoxazole- 5(4H)-ones using Na₂SO₃ as a catalyst. This choice of catalyst proved advantageous due to its non-hazardous and non-toxic nature, being a safe and easily handled food additive. The use of water as a solvent, environmentally friendly, allowed the reaction to proceed under mild conditions. The obtained products were pure with excellent yields. Additionally, all parts are accompanied by a recent, rich, and varied bibliography. Sun, 10 Nov 2024 00:00:00 GMT http://depot.umc.edu.dz/handle/123456789/14861 2024-11-10T00:00:00Z http://depot.umc.edu.dz/handle/123456789/14830 Investigation phytochimique et biologique de la propolis Algérienne. Daikh, Amina; Segueni, Narimane Our study is interested in the investigation of the chemical composition and the biological activities of Algerian propolis. In the first part of our study we examined several propolis harvested from Algerian East in order to compare their antibiofilm and cytotoxicity activities, In addition, the UPLC-ESI-MS/MS analysis of the most active extracts was also evaluated. In the second part we studied the antioxidant capacity of two other propolis by five different methods. The total phenolic and flavonoid contents were evaluated. Propolis of Mila exhibited the highest antioxydant activity. This result encouraged us to study the cytotoxicity activity of the extracts of this propolis. This propolis acts on MDA-MB- 231 cells by inducing apoptosis by increasing the concentrations of Bax, caspase 3 and p53 proteins as well and decreasing Bcl2 and CDK-4 proteins. These results are confirmed by the study of mRNA and cDNA. In the last part of our work we were interested in the chemical composition of Algerian propolis. After extraction, separation and purification, we obtained 6 pure flavonoids 5,4'-dihydroxy-6,7-dimethoxyflavone (Cirsimaritine), 7-methoxy 3,5 dihydroxyflavonol (Galangine 7-methoxy), 4',5,7-trihydroxy-3-methoxyflavone (isokampferide), 5,7-dihydroxy-flavanone (Pinocembrine), Apigenin 7-methoxy (Genkwanin) and Apigenin. Our study demonstrated that all the studied propolis are probably of t poplar type. Thu, 07 Dec 2023 00:00:00 GMT http://depot.umc.edu.dz/handle/123456789/14830 2023-12-07T00:00:00Z http://depot.umc.edu.dz/handle/123456789/14828 Synthèse, caractérisation, etude structurale par diffraction des rayons X et réactivité thermique des carboxylates à base d’alcalino-terreux. Bendjellal, Nassima; Boudaren, Chaouki The main purpose of this thesis is based on the synthesis and characterization of new coordination compounds based on alkaline-earth metals. Two synthesis methods were used to prepare these materials: synthesis by way of chemistry in solution and by solvothermal route. The structural study and physico-chemical characterization of these compounds was achieved by several techniques such as: spctroscopie IR, UV spectroscopy, X-ray fluorescence, crystal structures of materials hybrids have been solved by X-ray single crystal and thermal behaviors were studied by thermogravimetry, has fully describe the mechanisms of the decomposition of the solid. Likewise, the influence of the bond strength within the hydrogen-bonding network on both the structure stability has been evidenced within these architectures. Initially, the synthesis and the structural characterization by X-ray diffraction as well as the study of the physico-chemical and photophysical properties and the thermal stability by the use of cinnamic acid associated with the Co-ligand 1, 10’-phenthroline led to the production of four coordination polymers. In a second step, we describe the preparation of a dicarboxylate ligand on imidazolium H(S,S-diLeuIm) and the synthesis of three complexes by aqueous solution method based on K, Sr, Ba and characterized by methods IR, RMN spectroscopy and EM-MS mass. Tue, 20 Jun 2023 00:00:00 GMT http://depot.umc.edu.dz/handle/123456789/14828 2023-06-20T00:00:00Z