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New quinoxaline derivatives were prepared by the reaction of 2-hydroxyquinoxaline 1 and alkyl or alkylaminoalkyl halides in dimethylformamide using potassium carbonate as a base. The hydroxyl group was readily converted into a thiol function by treatment with phosphorus pentasulfide and/or Lawesson's reagent in pyridine, and the subsequent alkylation of the thiol group was carried out under phase-transfer catalyst conditions. Chlorination of 1 was carried out with phosphorus oxychloride. Branching of alkylamino side chains to the 2-OH, 2-SH, and 2-Cl quinoxalines resulted in the synthesis of several compounds. Synthesis and alkylation of 2-hydroxy 7-nitroquinoxaline are also reported. 相似文献
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Quinoxaline derivatives have been synthesized in a very short time with excellent yields by the condensation of 1,2-diamines with aliphatic or aromatic 1,2-dicarbonyl compounds or benzilmonoxime in the presence of silica sulfuric acid as a very inexpensive solid acid catalyst at room temperature. The recovery and reuse of the catalyst are also satisfactory. 相似文献
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Dhansay Dewangan Kartik Nakhate Achal Mishra Alok Singh Thakur Harish Rajak Jaya Dwivedi Swapnil Sharma Sarvesh Paliwal 《Journal of heterocyclic chemistry》2019,56(2):566-578
A series of quinoxalinone derivatives were synthesized by the reaction of o‐phenylenediamine with oxalic acid to yield 1, 4‐dihydro quinoxaline‐2, 3‐dione ( 1 ) and then treated with thionyl chloride to yield 2, 3 dichloro quinoxaline ( 2 ). This was further reacted with hydrazine hydrate to produce 2, 3‐dihydrazinyl quinoxaline ( 3 ). This was finally reacted with substituted aromatic aldehydes to produce 2,3‐bis[2‐(sustituted benzylidine) hydrazinyl] quinoxalines ( 4 ). These quinoxalinone derivatives were characterized by infrared spectroscopy and nuclear magnetic resonance spectroscopy and MASS spectral data. All the synthesized compounds were evaluated for their antimicrobial activity. The results of the antimicrobial study revealed that compounds 4c , 4d , and 4i were active and exhibited better inhibitory activities as compared to standard drug ciprofloxacin. The results were further checked with protein legend interaction by using docking studies, and all the compounds exhibited good docking scores between ?8.72 and ?11.29 kcal/mol against dihydrofolate reductase protein fragment from Staphylococcus aureus (PDB ID‐4XE6). Among all compound, 4c has shown maximum docking score and found in agreement to in vitro studies. 相似文献
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The oxidation reactions of a series of quinoxaline derivatives, using KMnO4 in the presence or absence of NaOH, are described. Neutral oxidation of 2-chloro- and 2, 3-dichloroquinoxalines 2 – 4 afforded the corresponding chloro- and dichloropyrazinedicarboxylic acids 13 and 14 in good yield. On the other hand, oxidation of quinoxalin-2(1H)-one and 1, 4-dihydroquinoxaline-2, 3-dione derivatives in alkaline medium gave different products, with the quinoxalin-2(1H)-one ( 5 ) forming 1, 4-dihydroquinoxaline-2, 3-dione ( 9 ), while various substituted quinoxalin-2, 3-dione derivatives (see 9 – 11 ) gave a new type of dimeric products. The structural assignments for the new compounds were based on spectroscopic data. 相似文献
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In this study, certain 3‐substituted styrylquinoxalin‐2(1H)‐ones ( 2a‐d ) and their 2‐chloro ( 3a‐d ) and 2‐piperazinyl derivatives ( 4a‐g ) were synthesized from 3‐methylquinoxalin‐2(1H)‐one ( 1 ). In addition, a series of 1‐alkyl‐3‐substituted styrylquinoxalin‐2(1H)‐ones ( 5a‐d ) was also prepared. Moreover, 3‐(N2‐arylidenehydrazinocarbonyl)quinoxalin‐2(1H)‐ones ( 8a‐c ) as well as their cyclized oxadiazolinyl derivatives ( 9a‐c ) were prepared from 3‐hydrazinocarbonylquinoxalin‐2(1H)‐one ( 7 ). Furthermore, 3‐(5‐substituted thio‐1,3,4‐oxadiazol‐2‐yl)quinoxalin‐2(1H)‐ones ( 11a‐c ) and ( 12a‐c ) were obtained from the intermediate compound ( 10 ) ‐ previously obtained via cyclization of ( 7 ) with CS2. Likewise, 3‐(5‐oxo‐4,5‐dihydro‐(1,3,4‐oxadiazol‐2‐yl)quinoxalin‐2(1H)‐one ( 13 ), 3‐[5‐(4‐nitrophenyl)‐1,3,4‐oxadiazol‐2‐yl]‐quinoxalin‐2(1H)‐one ( 14 ) and its 2‐chloro derivative ( 15 ) were prepared from 3‐hydrazinocarbonylquinoxalin‐2(1H)‐one ( 7 ). Some of these derivatives were evaluated for antimicrobial activity in vitro and some of the tested compounds showed antibacterial or antifungal activity. 相似文献
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A simple and rapid method for the preparation of a series of novel quinoxaline derivatives in the presence of Ag+ is reported. 相似文献
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Alexis A. Sosa Toa S. Rivera Mirta N. Blanco Luis R. Pizzio Gustavo P. Romanelli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1071-1079
Abstract A green, simple, and fast procedure has been developed for the preparation of quinoxaline derivatives by a condensation of 1,2-diamines with 1,2-dicarbonyl compounds in the presence of zirconium oxide modified with tungstophosphoric acid (H3PW12O40) as a heterogeneous catalyst, in a solvent-free medium using conventional heating. Quinoxaline derivatives were formed in short-time periods and excellent yields (65–100%). The reaction work-up is very simple and the catalyst can be easily separated from the reaction mixture and reused several times in subsequent reactions without appreciable loss of the catalytic activity. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional text. 相似文献
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熊果酸衍生物的合成、表征及其对癌细胞的抑制活性 总被引:1,自引:0,他引:1
以熊果酸为母体化合物,对其3-OH和17-COOH进行结构修饰,设计合成了9个熊果酸衍生物,其结构经IR、1H NMR和MS测试技术确证;噻唑蓝(MTT)比色法考察了所合成衍生物对体外人肝癌细胞HepG2培养增殖的抑制作用,结果显示受试衍生物均对细胞增殖有一定抑制作用,且呈剂量依赖性,其中衍生物9的抑制作用最强;衍生物9与细胞作用24 h后,经Hoechst 33342/PI双染色,倒置荧光显微镜下观察,出现细胞凋亡所具有的高蓝色/低红色荧光图;流式细胞术检测细胞周期发现:细胞被阻滞于S期,且阻滞作用随药物浓度的增加而增强。 相似文献
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Majid M. Heravi Khadijeh Bakhtiari Fatemeh F. Bamoharram Maryam H. Tehrani 《Monatshefte für Chemie / Chemical Monthly》2007,138(5):465-467
Summary.
Wells-Dawson heteropolyacid (H6P2W18O62 · 24H2O) was used as an effective catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation
of o-phenylenediamines with 1,2-dicarbonyl compounds at room temperature in excellent yields. 相似文献
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四硫富瓦烯衍生物/硬脂酸LB膜的表征 总被引:2,自引:0,他引:2
研究了四(苄硫基)四硫富瓦烯/硬脂酸(TBT-TTF/SA)(1:1)LB膜、二(亚乙二硫基)四硫富瓦烯/硬脂酸(BEDT-TTF/SA)(1:1)LB膜和四(十六烷硫基)四硫富瓦烯/硬脂酸(THT-TTF/SA)(1:1)LB膜的结构.从X射线衍射结果得到了LB膜的层间距离.X射线衍射图显示了TBT-TTF/SALB膜和BEDT-TTF/SALB膜的层间结构由硬脂酸控制.从偏振红外结果计算出硬脂酸和四硫富瓦烯衍生物在LB膜中的取向角.根据分子取向角确定了LB膜的层间结构.用分子长度和分子取向角得到的层间距离与从X射线衍射得到的层间距离相吻合. 相似文献
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Vesna Kunti? Maja Stanojevi? Ivanka Holclajtner-Antunovi? Sne?ana Uskokovi?-Markovi? Ubavka Mio? Marija Todorovi? Tanja Jovanovi? Vladana Vukojevi? 《Monatshefte für Chemie / Chemical Monthly》2006,43(9):803-810
Compounds of phosphotungstic acid (WPA) containing the amino acids alanine (WPA–Ala) or glycine (WPA–Gly) as counter cations were synthesized and characterized by elemental analysis, thermal analysis, and IR spectroscopy. Cellular
toxicity was assessed by the trypan blue exclusion method, and the antiviral activity of WPA and the modified WPA compounds was tested against herpes simplex viruses (HSV) type 1 and type 2. Biological assays indicate that the newly synthesized
compounds exhibit no evident cytotoxic effects on Vero cells and negligible antiviral activity against HSV-1 and HSV-2. 相似文献
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Vesna Kuntić Maja Stanojević Ivanka Holclajtner-Antunović Snežana Uskoković-Marković Ubavka Mioč Marija Todorović Tanja Jovanović Vladana Vukojević 《Monatshefte für Chemie / Chemical Monthly》2006,137(6):803-810
Summary. Compounds of phosphotungstic acid (WPA) containing the amino acids alanine (WPA–Ala) or glycine (WPA–Gly) as counter cations were synthesized and characterized by elemental analysis, thermal analysis, and IR spectroscopy. Cellular
toxicity was assessed by the trypan blue exclusion method, and the antiviral activity of WPA and the modified WPA compounds was tested against herpes simplex viruses (HSV) type 1 and type 2. Biological assays indicate that the newly synthesized
compounds exhibit no evident cytotoxic effects on Vero cells and negligible antiviral activity against HSV-1 and HSV-2. 相似文献
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The browning of plant-based food is commonly understood to result from the enzymatic polymerization of phenolic compounds to pigments, called melanin. However, during the thermal treatment of food, enzymes are deactivated, and non-enzymatic reactions predominate. The extent of the contribution of phenolic compounds to these non-enzymatic reactions has been speculated (“melanin-like vs. melanoidin-like”), but the literature is limited. Therefore, the aim of the present study was to investigate the heat-induced reactions of caffeic acid (CA), para-coumaric acid (CS), ferulic acid (FA), hydrocaffeic acid (HC), and 5-O-caffeoylquinic acid (CGA) under dry conditions. The model systems were characterized by color formation, reactant conversion, and antioxidant properties. Reaction products were analyzed by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy. Decarboxylation could be classified as the driving force for the observed color formation and was significantly impacted by the substitution of the aromatic system. Reaction products were found to contribute to an increase in the antioxidant properties of the model systems. The oligomers described in this study could be incorporated into food melanoidins, contributing to the color and antioxidant properties observed in roasted food rich in phenolic compounds, such as coffee or cocoa. 相似文献
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Ajeet A. Yelwande Madhukar E. Navgire Balasaheb R. Arbad Machhindra K. Lande 《中国化学会会志》2012,59(8):995-1000
Polyaniline/SiO2 nanocomposite material has been synthesized by using chemical oxidative method. Prepared catalytic material was characterized by means of transmission electron microscopy (TEM), thermal analysis (TG‐DTA), X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT‐IR). Solvent stability for the catalyst has been screened using UV‐Visible spectroscopy. Polyaniline/SiO2 catalyzed route has found to be an efficient and rapid protocol for the synthesis of quinoxaline derivatives by cyclocondensation of 1,2‐diketones and o‐phenylenediamines at room temperature. This protocol has several advantages such as high yield, good thermal stability, simple work up procedure, non‐toxic, clean, and easy recovery and reusability of the catalytic system. 相似文献