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王静馨  项续章 《分析化学》2002,30(4):507-507
1 引  言间二甲胺基苯甲酸是重要的染料、医药、农药和有机试剂的中间体 ,尤其是压敏和热敏染料结晶紫内酯的重要中间体之一。随着对结晶紫内酯的需求不断增长 ,国内近几年正在研究开发该产品。本文是伴随以间硝基苯甲酸为原料 ,加氢还原为间氨基苯甲酸 ,再以甲醛甲基化合成间二甲胺基苯甲酸的研究过程的分析测试研究。本方法适用于间二甲胺基苯甲酸产品检测及含有各种中间产物的过程检测。2 实验部分2 .1 仪器和试剂 Waters高效液相色谱仪 (包括 5 15泵 ;772 5I手动进样器 ,2 0 μL定量管 ;4 86紫外检测器 ) ,Anastar…  相似文献   

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通过手性胺拆分方法,从3-环己烯基甲酸出发分别合成得到了3-氨基环己基甲酸(ACHC)的四个立体异构体,以及cis-5-氨基-3-环己烯基甲酸(ACHEC)的二个立体异构体。  相似文献   

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以环氧氯丙烷为起始原料,经5步反应合成了3-羟基十四酸,总收率52.48%。以氯癸烷替代溴癸烷做格氏反应,有效地降低了偶联副产物的生成;从中间产物1-氯-2-羟基十三烷直接上氰基,避免了环化后上氰基时生成氢氰酸的危险。  相似文献   

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以甘草次酸(1)为原料,将其11位羰基还原、30位羧基酯化得11-脱氧甘草次酸-30-乙酯(3)。再以四氢呋喃为溶剂,N,N’-二环己基碳二亚胺(DCC)/4-二甲基氨基吡啶(DMAP)为偶合剂,选用Fmoc保护氨基酸对11-脱氧甘草次酸-30-乙酯的3位羟基进行酯化,得到11-脱氧甘草次酸-30-乙酯-3位氨基酸酯衍生物(4a~4d)。化合物4a~4d在V(CHCl2)∶V(Et2NH)=1∶1溶液中脱去Fmoc保护基得到最终产物(5a~5d),产率80%~87%。化合物5a~5d用1H NMR、EI-MS进行了表征。活性实验结果表明,化合物5a~5d对在高浓度二甲基甲酰胺下生长的枯草芽孢杆菌、大肠杆菌和酵母菌具有保护作用。  相似文献   

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Widdringtonia acid II, a common acidic constituent in Juniperus and Widdringtonia species, and 3β-hydroxcedrol were isolated front Juniperus squamata Lamb. Widdringtonia acid II was proved to be crystals derived from the 1:1 mixture of β-chamigrenic acid and hinokiic acid. The structures of β-chamigrenic acid and 3β-hydroxycedrol were established by chemical and physical evidence. In addition three other crystalline compounds, 7-oxototarol, hinokiol, and widdrol, were also identified.  相似文献   

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Widdringtonia acid II, a common acidic constituent in Juniperus and Widdringtonia species, and 3β-hydroxycedrol were isolated from juniperus squamata Lamb. Widdringtonia acid II was proved to be crystals derived from the 1:1 mixture of β-chamigrenic acid and hinokiic acid. The structures of β-chamigrenic acid and 3β-hydroxycedrol were established by chemical and physical evidence. In addition three other crystalline compounds, 7-oxototarol. hinokiol, and widdrol, were also identified.  相似文献   

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磷钨酸均相光催化还原降解水中偶氮染料酸性大红3R   总被引:5,自引:0,他引:5  
以磷钨酸(H3PW12O4记为PW12)作为光催化剂,在异丙醇作为电子给体的条件下对偶氮染料酸性大红3R(记为AR3R)进行光催化均相还原脱色研究。循环伏安法、暗反应、O2竞争抑制等实验表明杂多蓝(PW12O404-)对AR3R 具有明显的还原脱色作用。实验研究了催化剂PW12用量、异丙醇浓度、染料浓度、盐浓度对PW12/异丙醇光催化还原降解酸性大红3R的影响。结果表明:AR3R的光催化脱色速率随催化剂PW12、异丙醇浓度的增加而增加,最后趋于恒定;随染料初始浓度增加,初始光解速率增大,且符合Langmuir-Hinshelwood动力学方程;随盐浓度增加,染料脱色速率减小,表现为负的盐效应。由此推测AR3R与光反应生成的杂多蓝预先进行复合,然后发生电子转移引起偶氮染料还原脱色,杂多蓝氧化复原。本研究结果表明磷钨酸/异丙醇/UV绿色光催化还原体系能够有效用于偶氮染料废水的还原脱色处理。  相似文献   

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3-Bromopyruvic acid (3BP) is a potential anti-cancer drug, the action of which on cellular metabolism is not yet entirely clear. The presence of a bromine atom suggests that it is also reactive towards low-energy electrons, which are produced in large quantities during tumour radiation therapy. Detailed knowledge of the interaction of 3BP with secondary electrons is a prerequisite to gain a complete picture of the effects of 3BP in different forms of cancer therapy. Herein, dissociative electron attachment (DEA) to 3BP in the gas phase has been studied both experimentally by using a crossed-beam setup and theoretically through scattering and quantum chemical calculations. These results are complemented by a vacuum ultraviolet absorption spectrum. The main fragmentation channel is the formation of Br close to 0 eV and within several resonant features at 1.9 and 3–8 eV. At low electron energies, Br formation proceeds through σ* and π* shape resonances, and at higher energies through core-excited resonances. It is found that the electron-capture cross-section is clearly increased compared with that of non-brominated pyruvic acid, but, at the same time, fragmentation reactions through DEA are significantly altered as well. The 3BP transient negative ion is subject to a lower number of fragmentation reactions than those of pyruvic acid, which indicates that 3BP could indeed act by modifying the electron-transport chains within oxidative phosphorylation. It could also act as a radio-sensitiser.  相似文献   

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Baldev Singh 《合成通讯》2013,43(5):275-278
In the development of certain work in our laboratory, we needed large quantities of 3-nitrophenylacetic acid. This material is very expensive commercially. It therefore became necessary to find a convenient and efficient process since none of the reported procedures is suitable for a large scale preparation of 3-nitrophenylacetic acid. In the first synthesis reported by Frederick et al.1, 3-nitrobenzyl chloride was converted to 3-nitrophenylaceto-nitrile which was hydrolyzed to 3-nitrophenylacetic acid in 38% yield. The utility of this method for making large quantities of 3-nitrophenylacetic acid is restricted by the high cost of 3-nitrobenzyl halides. The second 2 method published by Jennings2 is a multistep process starting with 3-nitrobenzaldehyde and the reported overall yield is 31%. This method also is not suitable for a large scale preparation due to the hazardous nature of the acid azide which is formed as one of the intermediates in this five step sequence. The third method describes the conversion of 3-nitroacetophenone to 3-nitrophenyl-acetic acid by willgerodt reaction.3 Although the starting material 3-nitroacetophenone is inexpensive but the reported yield of 3-nitrophenylacetic acid is only 7%. The high temperature required in the willgerodt reaction causes the reduction of nitro group by sulfur resulting in a bad mixture thus lowering the yield of nitrothio-morpholide (3) and making its isolation difficult.  相似文献   

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3-甲基犬尿喹啉酸衍生物的合成   总被引:2,自引:0,他引:2  
张梅  杨凤志  邹新琢 《有机化学》2004,24(4):440-443
报道了六个具有潜在生物活性 3 甲基犬尿喹啉酸衍生物的合成 .它们以取代苯胺和 3 甲基 2 酮丁二酸二乙酯为起始原料 ,经加成脱水 ,环化而得到 .其中三个新的含氟化合物的结构分别经IR ,1 HNMR ,MS ,元素分析等表征  相似文献   

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该研究在前期已制备获得的拟除虫菊酯代谢物3-苯氧基苯甲酸(3-PBA)纳米抗体(Nb)基础上,将其进行生物素化,并利用多聚辣根过氧化物酶标记的链霉亲和素(polyHRP-SA)进行信号扩增,建立了基于生物素-亲和素系统高灵敏间接竞争ELISA检测3-PBA残留的分析方法。对抗原抗体工作浓度、缓冲液条件(pH值、离子浓度、吐温-20浓度)及polyHRP-SA浓度进行优化后,所建方法对3-PBA的半抑制浓度(IC50)为1.7 ng/mL,线性范围为0.37~7.4 ng/mL,检出限(LOD)为0.15 ng/mL。将该方法用于人尿样品(高温酸水解后固相萃取净化)和环境水样品(简单过滤)中3-PBA的检测,加标回收率分别为87.0%~127%和78.0%~113%,相对标准偏差(RSD)不大于10%。该方法具有灵敏度高、操作简便,适用于生物与环境样本中3-PBA的快速筛查。  相似文献   

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