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The selective transalkylation of N-methyl tertiary amines with 3,4-dibromobutenolides is described.The N-methyl group of the parent tertiary amines was replaced by alkenyl units of the butenolides;and a series of butenolide-containing tertiary enamines were obtained in moderate to good yields.Interestingly,the product 2b has shown a promising anticancer activity against HeLa cell lines(IC50=0.19 mmol/L). 相似文献
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含O2高温高压CO2环境中3Cr钢腐蚀产物膜特征 总被引:1,自引:0,他引:1
采用高温高压反应釜分别开展3Cr钢在CO2和O2共存、单独CO2和单独O2三种气体条件下的腐蚀实验,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能量色散X射线能谱(EDS)和电化学方法研究了3Cr钢在高温高压含有O2的CO2环境中的腐蚀产物膜特征.结果表明,在含有O2的CO2的条件下,3Cr钢表面腐蚀产物膜疏松多孔,主要成分为FeCO3、Fe3O4和Fe2O3,腐蚀产物中未见明显Cr元素富集,3Cr钢表现出点蚀的腐蚀形态.3Cr钢在高温高压含O2的CO2腐蚀条件下内外膜层电阻(Rf1、Rf2)和电荷传递电阻Rt均比仅含有CO2腐蚀环境的低,双电层电容(Cdl)和内外膜层电容(Cf1、Cf2)均比仅含有CO2腐蚀环境的高.含有O2的CO2条件下,其保护性显著低于单一CO2条件下形成的腐蚀产物膜.提出了在含O2的CO2气体条件下,3Cr钢表面存在由多种物质组成的腐蚀产物,这导致腐蚀产物疏松多孔,不会形成单一CO2条件下存在的显著提高腐蚀产物膜保护性的Cr(OH)3层,从而促进了3Cr钢的析氢腐蚀和酸性介质中的吸氧腐蚀的机理. 相似文献
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An efficient Pd-catalyzed intramolecular indole-C2-arylation protocol for the synthesis of pharmaceutically active bis-indole alkaloid analogues from simple and readily available and 3,3′-Bis(1H-indol-3-yl)methanes derivatives has been developed. The corresponding products could be obtained in moderate to excellent yields, which permits selective modification on either one of the two indole moieties independently. 相似文献
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Yiran Liu Meng Zhao Li-Peng Hou Zheng Li Chen-Xi Bi Zi-Xian Chen Qian Cheng Dr. Xue-Qiang Zhang Dr. Bo-Quan Li Prof. Stefan Kaskel Prof. Jia-Qi Huang 《Angewandte Chemie (International ed. in English)》2023,62(30):e202303363
Lithium–sulfur (Li–S) batteries are regarded as promising high-energy-density energy storage devices. However, the cycling stability of Li–S batteries is restricted by the parasitic reactions between Li metal anodes and soluble lithium polysulfides (LiPSs). Encapsulating LiPS electrolyte (EPSE) can efficiently suppress the parasitic reactions but inevitably sacrifices the cathode sulfur redox kinetics. To address the above dilemma, a redox comediation strategy for EPSE is proposed to realize high-energy-density and long-cycling Li–S batteries. Concretely, dimethyl diselenide (DMDSe) is employed as an efficient redox comediator to facilitate the sulfur redox kinetics in Li–S batteries with EPSE. DMDSe enhances the liquid–liquid and liquid–solid conversion kinetics of LiPS in EPSE while maintains the ability to alleviate the anode parasitic reactions from LiPSs. Consequently, a Li–S pouch cell with a high energy density of 359 Wh kg−1 at cell level and stable 37 cycles is realized. This work provides an effective redox comediation strategy for EPSE to simultaneously achieve high energy density and long cycling stability in Li–S batteries and inspires rational integration of multi-strategies for practical working batteries. 相似文献
36.
新型双氢青蒿素哌嗪-芳香酰胺类化合物的合成及其抗肿瘤活性的初步评价 总被引:1,自引:0,他引:1
以双氢青蒿素为起始原料,在草酰氯作用下无需分离,随后在"一锅煮"条件下与哌嗪作用得到胺类化合物,该类化合物与芳香酰氯作用,快速、高效地合成了6种新型芳酰胺类双氢青蒿素哌嗪衍生物。所有化合物通过IR、1H NMR、13C NMR和HR-MS得到结构确认。同时,以四甲基偶氮唑盐比色法(MTT法)研究了该类化合物对人肝癌细胞株SMMC-7721的抑制活性。初步研究结果表明,该类化合物具有明显抑制人肝癌细胞增殖、诱导其凋亡的细胞活性,给药72h,半抑制浓度IC50最优值仅为0.04μmol/L。在与青蒿素、双氢青蒿素的对比实验中发现,该类化合物的抗癌活性明显提高,表现出该类化合物具有潜在的开发和应用价值。 相似文献
37.
Direct alkylation of indoles and amines by tertiary enamides for the synthesis of pharmaceutically active 2-oxo-1-pyrrolidine analogues was described. With only a 0.5 mol% catalyst loading, molecular iodine was demonstrated to be efficiently enough to promote the reaction under neat condition. Only Markovnikov addition product was obtained indicating that the reactions proceeded with excellent regioselectivity. 相似文献
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