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41.
The viologen‐type dialdehyde of [N,N′‐bis(methylsalicylaldehyde)‐4,4′‐bipyridinium] dichloride (DA) was synthesized by reacting 5‐chloromethylsalicylaldehyde and 4,4′‐bipyridine. Then a new polymeric Schiff base ligand (PSBL) was synthesized by the condensation reaction of ethylenediamine and DA in methanol under reflux conditions. Afterwards, new ionic metallo‐Schiff base polymers (IMSPs) were synthesized by reacting PSBL with VO(acac)2, ZnCl2 and CuCl2 via coordination chelation. DA, PSBL and IMSPs were characterized using various analytical methods and spectral techniques. The solid‐state electrical conductivities of PSBL and IMSPs were studied. The electrical conductivity of these polymers at 300 K ranged from 1.30 × 10?5 to 4.52 × 10?10 Ω?1 m?1, which means they are potential organic and metallo‐organic semiconductors. 相似文献
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Saeidian Hamid Sadighian Hamed Arabgari Masomeh Mirjafary Zohreh Ayati Seyed Ebrahim Najafi Ezzatollah Moghaddam Firouz Matloubi 《Research on Chemical Intermediates》2018,44(1):601-612
Research on Chemical Intermediates - We report robust green synthesis of novel 1,2,3-triazole-based sulfonamides bearing different motifs such as fluorine under click conditions in presence of a... 相似文献
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Seyed Mohammad Seyedi Hamid Sadeghian Zohreh Safari 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2297-2306
The synthesis of β,β′-diketodithioethers 4b–j from corresponding β,β′-dihydroxydithioethers 3b–j was carried out by a Swern oxidation using DMSO-oxalyl chloride as oxidizing agent. β,β′-Dihydroxydithioethers 3b–j were prepared by the reaction of two molar equivalents of epoxides 1b–j with dimercaptoethane 2 in the presence of a saturated aqueous solution of potassium carbonate. The reactivity behavior of imine formation of the β,β′-diketodithioethers 4b–j by 2,4-dinitrophenylhydrazine was also investigated, and a mechanism was proposed by using molecular orbital (MO) calculations. To confirm the proposed mechanism, the role of the thia function to activate hydrazone formation by measuring HOMO-LUMO energy levels was also demonstrated. 相似文献
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Zohreh Mehri Lighvan Hossein Ali Khonakdar Abolfazl Heydari Mina Rafiee Maryam Dehdashti Jahromi Ali Derakhshani Amir Abbas Momtazi-Borojeni 《应用有机金属化学》2020,34(10):e5839
The organometallic palladium complex with nitrogen-containing heterocycles is a potent antitumor agent. Coordination of phosphorus ligands to organometallic complexes increases their hydrophilicity, promotes ligand−DNA interactions and damage level to cancer cells, and blocks division in target cells. In this study, a phosphaadamantane palladium complex ([Pd{(C,N)- (C12H8NH2)} (PTA) Cl], PTA = 1,3,5-Triaza-7-phosphaadamantane) ( 2 ) was synthesized via the reaction of biologically active PTA with binuclear palladacycles [Pd2{(C,N)-(C12H8NH2)}2(μ-Cl)2] ( 1 ). In vitro studies of the complex with DNA (calf-thymus) explored by UV–Vis, emission titration, circular dichroism and helix melting methods showed that the complex interacts with DNA via an intercalative mechanism. Furthermore, competitive binding studies using warfarin, digoxin and ibuprofen site markers containing definite binding sites revealed the binding of the complex to site I on bovine serum albumin. The in vitro release mechanism of the palladium complex exhibited a biphasic pattern characterized by an initial burst release followed by a slower sustained release. Ultimately, in vitro evaluation of cytotoxicity and cell death showed that the complexes were able to decrease the viability of human cancer cell lines (MCF-7 and Jurkat) in a dose-dependent manner, but lower decreases were observed in the viability of normal fibroblast cells ASF-4 at the dosages evaluated. Finally, the order of in vitro anticancer activities was found to be consistent with the DNA-binding affinities. 相似文献
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A covalently cross‐linked graphene oxide (GO) as a catalyst was prepared by a cross‐linking process using the nucleophilic reaction of zirconium (IV)‐coordinated 5,10,15,20‐tetrakis (aminophenyl)porphyrin (ZrPPh) with carboxyl groups of the edges of GO (GO‐ZrPPh). The chemical structure of catalyst was characterized by different analyses such as FT‐IR, SEM, TEM, EDS, ICP, TGA and UV. All analyses confirm the occurrence of successfully covalent immobilization of ZrPPh on the GO. Also, TEM and SEM images show that ZrPPh has been immobilized in the both of the edges and the basal plane of GO. The activity of the catalyst was studied for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones via Biginelli reaction. The cross‐linked catalyst is able to catalyze the reaction in short reaction times and good to excellent yields. 相似文献
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A facile and efficient synthesis of 1,5‐benzodiazepines with an arylsulfonamido substituent at C(3) is described. 1,5‐Benzodiazepine, derived from the condensation of benzene‐1,2‐diamine and diketene, reacts with an arylsulfonyl isocyanate via an enamine intermediate to produce the title compounds of potential synthetic and pharmacological interest in good yields (Scheme 1). In addition, reaction of benzene‐1,2‐diamine and diketene in the presence of benzoyl isothiocyanate leads to N‐[2‐(3‐benzoylthioureido)aryl]‐3‐oxobutanamide derivatives (Scheme 2). This reaction proceeds via an imine intermediate and ring opening of diazepine. The structures were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this type of cyclization is proposed (Scheme 3). 相似文献