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1.
发展了一条高效、简单的药物中间体β-卤代苯乙胺的合成方法.二苄胺和溴乙酸乙酯作为起始原料,经历取代、加成、催化氢化、氯代和酰化5步反应,以中等产率制备得到目标产物2-乙酰氨基-3-氯-3-(4-甲氧基苯基)丙酸乙酯,对合成过程中的中间产物及目标产物的制备进行了条件优化,确定了最佳反应路线,同时还通过熔点、核磁共振氢谱和碳谱对目标产物进行了表征.此合成方法为含多官能化苯乙胺结构的药物分子的合成提供了一种便利途径.  相似文献   

2.
通过合成一系列5,7-二取代-[1,2,4]三唑[1,5-a]嘧啶衍生物,对其体内抗癫痫活性进行研究.各种查尔酮和3-氨基-1,2,4-三氮唑在二甲基甲酰胺中加热反应分别得到5,7-二取代-4,7-二氢-[1,2,4]三唑[1,5-a]嘧啶(2a-2e)和它们的脱氢产物5,7-二取代-[1,2,4]三唑[1,5-a]嘧...  相似文献   

3.
在碳酸钾作用下, 采用乙酰乙酰胺类化合物与苯硫代异氰酸酯、 溴代乙酸乙酯在N,N-二甲基甲酰胺中反应, 合成了多取代2-氨基噻酚衍生物, 通过核磁共振、 红外光谱及元素分析方法对产物进行表征, 并对该反应机理进行初步探讨.  相似文献   

4.
文中以对叔丁基苯酚,1,2-二溴乙烷和二乙基二硫代氨基甲酸钠为主要原料,经过多步反应合成了两个下缘含有二硫代氨甲酰基结构单元的杯[4]芳烃衍生物:25,27-二[2-(N,N-二乙基氨基二硫代甲酰基)乙氧基]-26,28-二羟基对叔丁基杯[4]芳烃(化合物5)和25,27-二[2-(N,N-二乙基氨基二硫代甲酰基)乙氧基]-26,28-二羟基杯[4]芳烃(化合物6),并通过1H NM R和IR对化合物5和6的结构经进行了表征.合成条件优化实验结果表明,当以丙酮为溶剂时,25,27-二(2-溴乙氧基)-26,28-二羟基杯[4]芳烃(化合物4)与二乙基二硫代氨基甲酸钠的物质的量的比为1∶3.5、反应时间为16 h条件下,化合物6的产率最高可达75.3%.对化合物6光谱性质的初步研究表明其对Zn2+离子具有较好的识别能力.  相似文献   

5.
以7-氨基头孢烷酸(7-ACA)为原料,二氯甲烷和环己烷为溶剂,三甲基氯硅烷(TMSCl)为保护剂,与N-甲基吡咯烷(NMP)和三甲基碘硅烷(TMSI)制成的季铵盐中间体反应,脱保护后成盐得中间体7-氨基-3-(1-甲基-1-四氢吡咯)甲基-3-头孢-4-羧酸盐酸盐(7-MPCA),再与苯并噻唑硫醇活性酯反应,合成目标产物盐酸头孢吡肟。研究硅烷化反应、碘代反应和成盐反应的主要影响因素,进行工艺参数优化。采用红外光谱、元素分析、核磁共振谱和质谱对产物盐酸头孢吡肟进行结构表征。研究结果表明:该工艺原材料易得,反应条件温和,且操作简单,以7-ACA的质量计盐酸头孢吡肟的总收率为74.6%。  相似文献   

6.
为改善催化剂的溶解性能,以寻求更高效的光催化剂,以1,3-二亚氨基异吲哚啉和2, 3-二氰基-1, 4-二噻英为原料,用固相法合成了不对称型1, 4-二噻英-二苯基四氮杂卟啉铁FePcPz(dtn)4及其氯代改性FePcClPz(dtn)4. 对所得产物进行了UV-Vis、IR、X-射线光电子能谱 (XPS) 表征. 考察了产物的溶解性能,利用高效液相色谱法对产物进行了分离研究.  相似文献   

7.
以三羟甲基丙烷(TMP)和N,N-二羟乙基-3-胺基丙酸甲酯为单体,通过“准一步法”合成三代超支化聚胺-酯(HBP-OH),再与羟烷基硅油、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)和丙烯酸-β-羟乙酯(HEA)反应,合成了三代水溶性超支化光敏有机硅聚氨脂丙烯酸酯低聚物(WHBPSUA)。研究了反应温度、DMPA用量等因素对合成反应和产物性能的影响,确定了最佳反应条件,并通过IR、1H-NMR和GPC对超支化聚胺-酯及低聚物结构进行了表征。结果表明,三代超支化聚胺-酯(HBP-OH)最佳反应温度分别为120、130和135 ℃;DMPA和羟烷基硅油物质的量的比为1∶1时,所合成产物WHBPSUA具有良好的水溶性和成像性。  相似文献   

8.
通过4-羟基-4'-二甲氨基查尔酮和S-十二烷基-S'-(α,α'-二甲基-α″-乙酸)-三硫代碳酸酯在缩合剂DCC(二环己基碳二亚胺)和促进剂DMAP(4-二甲氨基吡啶)作用下,合成了含二甲氨基查尔酮基团的三硫代碳酸酯,并通过熔点、红外光谱、紫外光谱和核磁共振氢谱对其结构进行了表征。研究了该化合物在不同极性溶剂中的发光特性,结果表明,随着溶剂极性增加,含二甲氨基查尔酮基团的三硫代碳酸酯的紫外-可见特征吸收波长和荧光发射波长均发生红移,荧光强度呈现先升高后下降的特点,其荧光具有溶剂极性敏感的特性。  相似文献   

9.
本文系统研究了新合成化合物8-氨基喹啉-5-偶氮苯(AQAP)、8-氨基喹啉-5-偶氮对氯代苯(CI-AP)、8-氨基喹啉-5-偶氮对溴代苯(Br-AP)作为荧光试剂水相测定痕量铜(Ⅱ)的最佳分析条件:测定用波长分别选定为APAQ-Cu(Ⅱ)365nm/320nm,  相似文献   

10.
采用发散式合成法,通过重复以氨基为端基的整代产物与丙烯酸甲酯进行的Michael加成反应和以酯基为端基的半代产物与乙二胺进行的酰胺化反应两个步骤,得到一系列接枝不同代数超支化聚酰胺-胺(PAMAM)分子的改性埃洛石纳米管(HNTs).利用傅里叶变换红外光谱、X射线光电子能谱、X射线衍射、热重分析和透射电镜对产物进行了表...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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