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91.
Ashraf A. Aly Stefan Brse Alaa A. Hassan Nasr K. Mohamed Lamiaa E. Abd El-Haleem Martin Nieger Nesrin M. Morsy Mohammed B. Alshammari Mahmoud A. A. Ibrahim Elshimaa M. N. Abdelhafez 《Molecules (Basel, Switzerland)》2020,25(23)
Three new series of paracyclophanyl-dihydronaphtho[2,3-d]thiazoles and paracyclophanyl-thiazolium bromides were designed, synthesized, and characterized by their spectroscopic data, along with X-ray analysis. One-dose assay results of anticancer activity indicated that 3a–e had the highest ability to inhibit the proliferation of different cancer cell lines. Moreover, the hybrids 3c–e were selected for five-dose analyses to demonstrate a broad spectrum of antitumor activity without apparent selectivity. Interestingly, series I compounds (Z)-N-substituted-4,9-dihydronaphtho[2,3-d]thiazol-3(2H)-yl)-4′-[2.2]paracyclophanylamide) that are carrying 1,4-dihydronaphthoquinone were more active as antiproliferative agents than their naphthalene-containing congeners (series II: substituted 2-(4′-[2.2]paracyclophanyl)hydrazinyl)-4-(naphth-2-yl)-thiazol-3-ium bromide hybrids) and (series III: 3-(4′-[2.2]paracyclophanyl)amido-2-(cyclopropylamino)-4-(naphth-2-yl)thiazol-3-ium bromide) toward the SK-MEL-5 melanoma cell line. Further antiproliferation investigations of 3c and 3e on the healthy, normal unaffected SK-MEL-5 cell line indicated their relative safety. Compound 3c showed an inhibition of eight isoforms of cyclin-dependent kinases (CDK); however, it exhibited the lowest IC50 of 54.8 nM on CDK1 in comparison to Dinaciclib as a reference. Additionally, compound 3c revealed a remarkable downregulation of phospho-Tyr15 with a level (7.45 pg/mL) close to the reference. 3c mainly showed cell cycle arrest in the pre-G1 and G2/M phases upon analysis of the SK-MEL-5 cell line. The sequential caspase-3 assay for 3c indicated a remarkable overexpression level. Finally, a molecular docking study was adopted to elucidate the binding mode and interactions of the target compounds with CDK1. 相似文献
92.
Mahmoud Farouk Salman A. Alrokayan Ahamad Imran Khalid M. Abu-Salah Mohamed Ghazzali Khalid A. Al-Farhan Salem El-Gohary Mamdouh Adly 《Chemical Papers》2013,67(2):229-235
3-Substituted quinazoline-2,4(1H,3H)-dione and 2,3-di-substituted quinazolineone derivatives attract considerable interest due to their pharmacological properties. In this paper, we report the synthesis of N-substituted-3-nitrophthalimide derivatives II?CIII, the reactions of phthalimide III with amines, hydrazines, and amino acid derivatives to synthesise a small library of 3-substituted-5-nitroquinazoline-2,4(1H,3H)-diones IV?CXIV and 2,3-di-substituted-6-nitro-quinazolineones XVIII?CXIX. 相似文献
93.
El-Wahab AH Al-Fifi ZI Bedair AH Ali FM Halawa AH El-Agrody AM 《Molecules (Basel, Switzerland)》2011,16(1):307-318
Vilsmeier formylation of 2-(1-phenylhydrazonoethyl)naphtho[2,1-b]furan (2) gave 3-naphtho[2,1-b]furan-2-yl-1-phenyl-1H-pyrazole-4-carbaldehyde (3), which was reacted with C- and N-nucleophiles to afford naphthofuranpyrazol derivatives 4-8. Treatment of 2-[(3-(naphtho[2,1-b]furan-2-yl)-1-phenyl-1H-pyrazol-4-yl)methylene]-malononitrile (4a) with reactants having active hydrogen and Et?N gave the corresponding pyrazoline, pyran and chromene addition product derivatives 10, 12 and 13, consisting of three different connected heterocyclic moieties. Reaction of 1-((3-(naphtho[2,1-b]furan-2-yl)-1-phenyl-1H-pyrazol-4-yl) methylene)-2-phenylhydrazone (6b) with AcONa and ethyl bromoacetate or chloroacetone afforded the thiazolidinone and methylthiazole derivatives 14 and 15, respectively. In addition, intramolecular cyclization of 6d with Ac?O afford the corresponding 1,3,4-thiadiazol-2-yl acetamide derivative 16. The structures of the synthesized compounds were confirmed by IR, 1H-NMR/13C-NMR and mass spectral studies. Compound 14 showed promising effects against the tested Gram positive and negative bacteria and fungi. 相似文献
94.
95.
Brik A Ficht S Yang YY Bennett CS Wong CH 《Journal of the American Chemical Society》2006,128(46):15026-15033
A novel method for the synthesis of N-linked glycopeptides using the sugar-assisted ligation strategy from cysteine free peptides is presented. The ligation junction tolerates a variety of amino acids, favoring less hindered amino acids and those with side chains that could serve as a general base in the ligation pathway. Since our approach allows the ligation of difficult junctions, the method could be applied to the synthesis of large peptides by enzymatic removal of the sugar moiety. Alternatively, more complex glycopeptides can be synthesized using glycosyltransferases. Together, this sequence of reactions should be amenable to the synthesis of glycopeptides and glycoproteins and their deglycosylated products. 相似文献
96.
Rosenani A. Haque Abbas Washeel Salman Srinivasa Budagumpi Amirul Al‐Ashraf Abdullah Zena A. Abdul Hameed Al‐Mudaris Amin M. S. Abdul Majid 《应用有机金属化学》2013,27(8):465-473
A series of Ag(I) complexes ( 6 , 7 , 8 , 9 ) derived from imidazol‐2‐ylidenes was synthesized by reacting Ag2O with an o‐, m‐, p‐xylyl or 1,3,5‐triazine‐linked imidazolium salts ( 1 , 2 , 3 , 4 ) and then characterizing these using various spectro‐analytical techniques. Additionally, triazine‐linked bis‐imidazolium salt 5 was characterized using the single‐crystal X‐ray diffraction method. Complexes 6–9 were formed from the N‐heterocyclic carbene ligand precursors 1–3 as PF6‐ salts in good yields. Conversely, salt 5 does not form Ag(I) complex even under various reaction conditions. Using ampicillin as a standard, complexes 6–9 were tested against bacteria strains Escherichia coli and Staphylococcus aureus as Gram‐negative and Gram‐positive bacteria, respectively, showing potent antimicrobial activities against the tested bacteria even at minimum inhibition concentration and bacterial concentration levels. Furthermore, the potential anticancer activities of the reported complexes were evaluated against the human colorectal cancer (HCT 116) cell lines, using 5‐fluorouracil as a standard drug. The highest anticancer activities were observed for complex 8 with an IC50 value of 3.4 μm , whereas the lowest was observed for complex 9 with an IC50 value of 18.1 μm . Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
97.
1,4‐Dioxo‐1,4‐dihydronaphthalene‐2,3‐dicarbonitrile and 1,1,2,2‐Tetracyanoethene in Heterocyclization 下载免费PDF全文
Ashraf A. Aly 《Journal of heterocyclic chemistry》2015,52(4):974-989
This survey is mainly concerned with selected reactions of 1,4‐dioxo‐1,4‐dihydronaphthalene‐2,3‐dicarbonitrile and 1,1,2,2‐tetracyanoethene, which have use or potential use in heterocyclic synthesis. 相似文献
98.
Ya‐Ching Shen Pei‐Show Shih Yun‐Sheng Lin Yu‐Chi Lin Yao‐Haur Kuo Yuh‐Chi Kuo Ashraf Taha Khalil 《Helvetica chimica acta》2009,92(10):2101-2110
Chemical investigation of the sponge Ircinia formosana resulted in the isolation of seven new linear C22‐sesterterpenoids, irciformonins E–K ( 1 – 7 ) in addition to irciformonin A ( 8 ), a previously isolated furanosesterterpenoid (=a furan‐moiety‐containing sesterterpenoid) from the same species. The structures were determined by interpretation of HR‐ESI‐MS and 2D‐NMR spectra. The structure of irciformonin A ( 8 ) was revised. Compound 5 exhibited significant inhibition of peripheral blood mononuclear cell proliferation induced by phytohemaglutinin. 相似文献
99.
100.
Ashraf A. Mohamed 《Monatshefte für Chemie / Chemical Monthly》2009,375(5):9-14