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71.
Abd El Raheim M. Donia Gamal A. Soliman Ahmed M. Zaghloul Saleh I. Alqasoumi Amani S. Awaad Asmaa M. Radwan Omer A. Basodan 《Journal of Saudi Chemical Society》2013,17(1):125-133
The aim of the present study was to investigate the chemical constituents and hepatoprotective effect of Ficus ingens (Miq.) Miq. (Moraceae) extract against carbon tetrachloride-induced acute liver damage in male Wistar albino rats. The ethanol extract of F. ingens, was subjected to phytochemical study. In addition, its acute and sub-chronic toxicities were assessed. Eight compounds were isolated from this plant and identified as β-sitosterol, β-sitosterol glucoside, chryasophanol, 7-hydroxy-2,5 dimethyl chromen-4-one, quercetin, Aloe emodin glucoside, rutin and Patuletin-3′-O-methyl-3-O-rutinoside. The structure elucidation was based on 1H and 13C NMR, proton–proton correlation spectroscopy (1H–1H Cosy), distortionless enhancement by polarization transfer (DEPT), Heteronuclear Multiple-Quantum Correlation (HMQC), and heteronuclear multiple bond correlations spectrum (HMBC). Hepatotoxicity induced with CCl4 was evidenced by elevation of liver marker enzymes (ALT, AST, ALP and LDH) and TB content in serum. In addition, antioxidant enzymes were drastically inhibited with significant reduction of GSH and increased LPO in liver homogenate of CCl4-intoxicated rats. Pre-treatment with F. ingens (200 and 400 mg/kg) and silymarin (50 mg/kg) avoided the changes observed in CCl4-intoxicated rats. In conclusion, the ethanol extract of F. ingens showed protective activity against liver injury, which might be developed into a new hepatoprotective agent. 相似文献
72.
2‐Cyanoacetamido‐4‐methylthiazole ( 1 ) was utilized as a versatile precursor for the construction of new thiazole clubbed thiazolidine, thiophene, pyridine, or chromene scaffold. The base‐catalyzed addition of 1 to phenyl isothiocyanate followed by subsequent treatment of the produced thiocarbamoyl intermediate with ethyl chloroacetate or chloroacetonitrile furnished the corresponding thiazolyl‐thiazolidine and thiazolyl‐thiophene hybrids. The reactions of compound 1 with chemical reagents, namely, acetylacetone, malononitrile, and/or 2‐(4‐anisylidene)‐malononitrile have been studied and furnished the corresponding thiazole‐pyridine hydrides 8 – 10 . Furthermore, treatment of the precursor 1 with salicylaldehyde, various aryl diazonium chlorides, and/or aromatic aldehydes afforded their corresponding thiazolyl‐chromene hybrid 12 , arylhydrazono‐nitriles 13 , and unsaturated nitriles 14 , respectively. The cytotoxicity of the synthesized compounds was screened against the cell lines HepG2, HCT‐116, and MCF‐7. Compounds 8 , 10 , and 12 recorded the best results, which was illustrated by molecular docking. Molecular Operating Environment molecular docking calculations carried out here is to rationalize correlation between docking results and biological data of thymidylate synthase (Protein Data Bank code: IHVY) inhibition. Docking has been carried out in the same co‐crystallographic inhibitor binding site to predict if the binding mode of active compounds is analogous to that of native inhibitor. 相似文献
73.
Yousri D. A. AbdelAty Amr M. Said Lobna A. Elwakil A. S. Maundy Brent Radwan Ahmed G. 《Nonlinear dynamics》2019,95(3):2491-2542
Nonlinear Dynamics - Fractional-order chaotic systems (FOCS) parameter identification is an essential issue in chaos control and synchronization process. In this paper, different recent... 相似文献
74.
Ashraf A. Aly Alan B. Brown Mohamed Abdel‐Aziz Gamal El‐Din A. A. Abuo‐Rahma Mohamed F. Radwan Mohamed Ramadan Amira M. Gamal‐Eldeen 《Journal of heterocyclic chemistry》2012,49(4):726-731
Reaction of 3‐aroyl‐1‐arylthioureas with dimethyl but‐2‐ynedioate in dichloromethane and catalyzed by triphenylphosphine at ?5°C led to (Z)‐methyl 2‐[(Z)‐2‐(4‐aroylimino)‐4‐oxo‐3‐aryl‐1,3‐thiazolidin‐5‐ylidene]acetates in good yields. The mechanism is discussed. X‐ray structure analysis of one thiazolidine derivative is described. Antitumor and antioxidant activities have been investigated. One derivative of 1,3‐thiazolidine showed moderate antiproliferative in vitro activity against hepatocellular carcinoma Hep‐G2, whereas another 1,3‐thiazolidine introduced effective antioxidant activity compared to ascorbic acid. 相似文献
75.
Low levels of fetal calf serum (FCS), used as protein supplement in cell culture medium, were traced in preparations of primary murine macrophages (bone-marrow-derived macrophages (BMM) and peritoneal macrophages (PM)). Main components of this common additive were mapped in 2-DE by means of differential image gel electrophoresis and immunoblotting. Additional washing steps in cell preparation helped to decrease the levels of the four highest abundance foetal serum proteins (serum albumin (SA), alpha1-fetoprotein (AFP), alpha1-antitrypsin (alpha1AT) and transferrin (Tf)) to less than 1% of total protein. Macrophage spot pattern was recorded in parallel and showed little variation. Results presented are supposed to be of general interest for cell preparations with similar background. 相似文献
76.
77.
Ahmed F. Saber Remon M. Zaki Adel M. Kamal El-Dean Shaban M. Radwan 《Journal of heterocyclic chemistry》2020,57(1):238-247
The starting compound 4-amino-3-methyl-1-phenyl-1H-thieno[2,3-c]pyrazole-5-carboxamide (1) , that has been previously synthesized according to the literature procedure, underwent a reaction with the anhydride of phthalic acid either in AcOH or DMF to give isoindolinylpyrazole-5-carboxamide 3 and pyrazolothienopyrimidoisoindoledione 4 , respectively. Also, it was subjected to react with diethylmalonate followed by hydrazinolysis by hydrazine hydrate to yield the pyrazolothienopyrimidinyl acetohydrazide 5 . The carbohydrazide derivative 5 was used as a key intermediate for the preparation of other new heterocyclic systems containing pyrazolylacetyl pyrazolothienopyrimidines and pyrazolothieno-pyrimidotriazepine compounds 6–11 . The structures of these new heterocycles have been characterized by using analytical and spectroscopic analyses (IR, 1H-NMR, 13C-NMR and MS). Some derivatives of the synthesized compounds exhibited remarkable antibacterial and antifungal activities against many bacterial and fungal strains. 相似文献
78.
Nermeen A. Eltahawy Amany K. Ibrahim Mohamed M. Radwan Mahmoud A. ElSohly Hashim A. Hassanean Safwat A. Ahmed 《Tetrahedron letters》2014
Chemical investigation of the Red Sea soft coral Sarcophyton auritum led to the isolation and structure elucidation of two new diterpene cembranoids; 2-epi-sarcophine (2) and (1R,2E,4S,6E,8R,11R,12R)-2,6-cembradiene-4,8,11,12-tetrol (4), as well as two known diterpene cembranoids, reported for the first time from this species, namely sarcophine (1) and (+)-7α,8β-dihydroxydeepoxysarcophine (3). Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. The isolated cembranoids were found to display high cytotoxicity against HepG2 (liver cancer cell line) and MCF-7 (breast cancer cell line). 相似文献
79.
M. M. Ghorab M. A. A. Radwan N. M. H. Taha N. E. Amin M. A. Shehab I. M. I. Faker 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2906-2917
The reaction of 4,4′-diisothiocyanato-1,1-diphenylsulfone 2 with aromatic amines and phenol derivatives afforded the corresponding thioureio derivatives 3–9 , respectively. Also, the reaction of 2 with catechol gave the corresponding carbamothioate derivative 11. Quinazoline derivatives 14 and 15 were obtained in good yield via reaction of 2 with anthranlic acid derivatives. Imidazolidine biscompounds 16 and 17 were readily synthesized from the reaction of 2 with N-(4-substituted-phenyl)cyanothioformanilides. The structure of the products was confirmed from elemental analysis as well as spectral data. Most of the synthesized compounds showed remarkable antimicrobial activity compared with chloramphenicol and Grisofluvine as positive controls. Compound 6 was almost as active an antitumor agent as the reference drug Doxorubicin. 相似文献
80.
A. M. Kamal El-Dean A. M. Elkhawaga Sh. M. Radwan M. M. Ahmed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):2034-2048
Mercaptomethylpyrazolopyrimidine (2) was synthesized and reacted with ethyl chloroacetate to afford ethyl pyrazolpyrimidinylmethylmercapto acetate ( 3) , which in turn was converted into the corresponding carbohydrazide 4 . Carbohydrazide 4 reacts with a variety of reagents to give different pyrazolopyrimidines ( 5–12 ). Chloromethyl-pyrazolopyrimidine (1) reacts with chloropyridine to give compound 13 , which was subjected in a series of reactions to give new compounds 14–20 . 相似文献