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1.
5-氟尿嘧啶乙酸对-硝基苯酯和5-氟尿嘧啶丙酸对-硝基苯酯分别与三种二肽反应,制备了五个5-氟尿嘧啶二肽(4 a-e)。以5-氟尿嘧啶的氨基酸对-硝基苯酯(2 a-c)分别和三种二肽反应,制得四个5-氟尿嘧啶三肽(5 a-d)。产物经元素分析、NMR、IR和UV鉴定。初步动物试验表明:5-氟尿嘧啶丙酰甘-苯丙二肽,5-氟尿嘧啶乙酰甘-甘-苯丙三肽和5-氟尿嘧啶乙酰缬-亮-甘三肽对小白鼠移植性艾氏腹水癌有一定的抑制作用。  相似文献   

2.
5-氟尿嘧啶乙酸对-硝基苯酯和5-氟尿嘧啶丙酸对-硝基苯酯分别与三种二肽反应,制备了五个5-氟尿嘧啶二肽(4aα-e).以5-氟尿嘧啶的氨基酸对-硝基苯酯(2a-c)分别和三种二肽反应,制得四个5-氟尿嘧啶三肽(5A-d).产物经元素分析,NMR,IR和UV鉴定.初步动物试验表明:5-氟尿嘧啶丙酰甘-苯丙二肽,5-氟尿嘧啶乙酰甘-甘-苯丙三肽和5-氟尿嘧啶乙酰缬-亮-甘三肽对小白鼠移植性艾氏腹水癌有一定的抑制作用.  相似文献   

3.
肿瘤细胞与正常细胞在酶系上存在差别,利用这些差别,chakravarty等设计并合成缬-亮-赖三肽与苯二胺氮芥等抗肿瘤原药结合的抗肿瘤短肽药物,它们的抗肿瘤选择性比苯二胺氮芥等抗肿瘤原药提高5~7倍。我们在前文中报道了5-氟尿嘧啶乙酰(丙酰)二肽和三肽的合成及抗动物肿瘤试验,初步结果表  相似文献   

4.
张兴  郑炎松 《合成化学》2012,(3):396-398
以N-Boc-L-缬氨酸为起始原料,经四步反应(最后一步用苯丙酰氯为苯丙酰化试剂)高产率地合成了蛋白质MyD88的小分子拟似物——N-(N’-3-苯丙酰-L-缬氨酰)四氢吡咯(AS-1),其结构经1H NMR和MS确证,总收率42%,纯度高于98%。  相似文献   

5.
以N-Boc-L-缬氨酸为起始原料,经四步反应(最后一步用苯丙酰氯为苯丙酰化试剂)高产率地合成了蛋白质MyD88的小分子拟似物—N-(N′-3-苯丙酰-L-缬氨酰)四氢吡咯(AS-1),其结构经1H NMR和MS确证,总收率42%,纯度高于98%.  相似文献   

6.
本文报告带保护基的牛胰岛素A链羧端的十二肽Ⅰ(N-苄氧羰基缬氨酰-S-苄基半胱氨酰-丝氨酰-亮氨酰-酪氨酰-谷氨酰胺酰-亮氨酰-γ-甲酯谷氨酰-天冬酰胺酰-酪氨酰-S-苄基半胱氨酰-天冬酰胺甲酯)和十六肽Ⅱ(N-苄氧羰基-S-苄基半胱氨酰-S-苄基半胱氨酰-丙氨酰-丝氨酰-缬氨酰-S-苄基半胱氨酰-丝氨酰-亮氨酰-酪氨酰-谷氨酰胺酰-亮氨酰-γ-甲酯谷氨酰-天冬酰胺酰-酪氨酰-S-苄基半胱氨酰-天冬酰胺甲酯)的合成. 肽Ⅰ和Ⅱ是由前文合成的带保护基的九肽Ⅳ(N-苄氧羰基亮氨酰-酪氨酰-谷氨酰胺酰-亮氨酰-γ-甲酶谷氨酰-天冬酰胺酰-酪氨酰-S-苄基半胱氨酰-天冬酰胺甲酯)经溴化氢-乙酸法脱去N-保护基后按迭氮化合物法分别与三肽酰肼Ⅴ(N-苄氧羰基缬氨酰-S-苄基半胱氨酰-丝氨酰肼)和七肽酰肼Ⅷ(N-苄氧羰基-S-苄基半胱氨酰-S-苄基半胱氮酰-丙氨酰-丝氨酰-缬氨酰-S-苄基半胱氨酰-丝氨酰肼)缩合而得. 肽Ⅰ和Ⅱ经元素分析及氨基酸组成分析证明为分析纯.由于它们是由光学纯L型的肽Ⅳ,Ⅴ,Ⅷ等经迭氮化合物法缩合而成,因此肽Ⅰ和Ⅱ很可能皆为光学纯L型.肽Ⅰ能被亮氨酸氨肽酶水解为相应的组成氨基酸而不留显著的茚三酮阳性的残肽.  相似文献   

7.
张雁  冯小明 《合成化学》1999,7(2):125-127
用一锅法制得了2-三溴甲基-3甲酰基-4甲基-5氧-恶唑烷酮,它与脯氨酸甲酯及其它氨基酸酯反应生成N-甲基-L-丙氨酰脯氨酸甲酯和系列N-甲基-L-丙氨酰的二肽。  相似文献   

8.
李叶芝  郭纯孝 《合成化学》1998,6(2):155-160
R-四氢噻唑-2-硫酮-4-羧酸同R.S-亮氨醇、R.S-蛋氨醇、R.S-苯丙氨醇和R.S-色氨醇反应分别得到光学活性非对映体过剩的铵盐;R-四氢噻唑-2-硫酮-4-羧酸.S-色氨醇,同时分离出光学活性对映体过剩的R-亮氨醇,S-氨蛋醇,S-苯丙氨醇及R-色氨醇,用半经验的量子化学PM3方法研究了氨基醇的最优构型和电子结构,得到了铵盐的最优几何构型。  相似文献   

9.
本文以四-(对氨基苯基)卟啉和N-氯乙酰缬氨酸为原料,在DMF中首次合成了一种新型的含二肽基团的四苯基卟啉,四-(对甘-缬二肽苯基)卟啉(H2L),及其Mn(Ⅲ)、Fe(Ⅲ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Zn(Ⅱ)配合物MnLCl, FeLCl, CoL, NiL, CuL, ZnL,用元素分析、红外光谱、电子光谱、荧光光谱、氢核磁共振谱和激光拉曼光谱进行了表征,研究了这些新型配合物与含N、S碱的轴向加合性质。  相似文献   

10.
本文叙述带保护基的牛胰岛素A链氨端五肽Ⅰ(N-苄氧羰基甘氨酰-异亮氨酰-缬氨酰-γ-叔丁酯谷氨酰-谷氨酰胺酰肼基甲酸叔丁酯)及九肽Ⅱ(N-苄氧羰基甘氨酰-异亮氨酰-缬氨酰-谷氨酰-谷氨酰胺酰-S-苄基半胱氨酰-S-苄基半胱氨酰-丙氨酰-丝氨酰脐)的合成。Ⅰ是由已知三肽Ⅲ(N-苄氧羰基异亮氨酰-缬氨酰-γ-叔丁酯谷氨酸乙酯)经二种不同的合成步骤分别缩合而得,五肽Ⅰ经三氟乙酸脱去γ-叔丁基和N-叔丁氧羰基后与已知四肽Ⅷ(S-苄基半胱氨酰-S-苄基半胱氨酰-丙氨酰-O-乙酰丝氨酸甲酯溴氢酸盐)借迭氮法缩合而得九肽酯Ⅸ再经肼解而得九肽肼Ⅱ。合成的三肽、四肽、五肽和九肽的化学纯度曾经纸层析、纸电泳、元素分析及氨基酸组成分析证明,其光学纯度(除九肽Ⅱ和Ⅸ外)皆曾经亮氨酸氨肽酶水解及水解物的氨基酸组成测定证明为L型,九肽Ⅸ是由光学纯L型的肽Ⅰ与Ⅷ经迭氦法缩合而成,因此Ⅸ以及Ⅱ很可能为光学纯L型。  相似文献   

11.
l-Proline-based cyclic dipeptides were synthesized from N-Boc-protected dipeptide methyl esters under catalyst-free condition using water as a solvent. One-pot deprotection and cyclization have been used as the key steps, providing an efficient and environmentally friendly approach. Clean reaction conditions, easy isolation, and good yields of cyclic dipeptides are the salient features of the proposed methodology.  相似文献   

12.
多相酶膜反应器合成生物活性二肽   总被引:2,自引:0,他引:2  
生物活性肽;多相酶膜反应器合成生物活性二肽  相似文献   

13.
Copper selenide films with different phase and morphology were synthesized on copper substrate through controlling reaction solvent by microwave-assisted nonaqueous approach. The films were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The result showed that the pure films could be obtained using cyclohexyl alcohol or benzyl alcohol as solvent. The cubic Cu2−xSe dendrites were synthesized in cyclohexyl alcohol reaction system and hexagonal CuSe flaky crystals were obtained with benzyl alcohol as solvent.  相似文献   

14.
The first efficient intermolecular reaction of gold carbene intermediates generated via gold-catalyzed alkyne oxidation has been realized using nitriles as both the reacting partner and the reaction solvent, offering a generally efficient synthesis of 2,5-disubstituted oxazoles with broad substrate scope. The overall reaction is a [2 + 2 + 1] annulation of a terminal alkyne, a nitrile, and an oxygen atom from an oxidant. The reaction conditions are exceptionally mild, and a range of functional groups are easily tolerated. With complex and/or expensive nitriles, only 3 equiv could be sufficient to achieve serviceable yields in the absence of any solvent and using only 1 mol % BrettPhosAuNTf(2) as the catalyst.  相似文献   

15.
Procedures were developed for reducing the reaction time and improving the yield of reductive alkylation in solid phase pseudopeptide synthesis by utilizing microwave irradiation. We chose dipeptides containing the reduced amide bond ψ[CH2NH] as a model system and optimized the microwave assisted reductive alkylation reaction in solid phase pseudopeptide synthesis using Fmoc chemistry. Under the optimized condition, the reductive alkylation reaction used for incorporating the reduced amide bond into the dipeptides was completed in only 8.5 min, whereas the normal reductive alkylation reaction required a total of 300 min. The purity and yield of the various dipeptides containing the reduced amide bond synthesized in this way are better than those achieved using the reductive alkylation method without microwave irradiation. We chose α helical peptides, which are known as a difficult sequence to synthesize, and incorporated the reduced amide bond by the microwave-assisted reductive alkylation reaction. We successfully synthesized pseudopeptides containing the reduced amide bond as a major product by using the novel microwave-assisted method, whereas the same products were obtained as a minor product when using the reductive alkylation method without microwave irradiation.  相似文献   

16.
The title compound, C10H20N3O4·1.094H2O, crystallizes with two dipeptide molecules in the asymmetric unit, each participating in two head‐to‐tail chains with hydrogen bonds between the terminal amino and carboxylate groups. As with many other dipeptides, the resulting structure is divided into distinct layers, but as the amide groups of the two peptide molecules participate in different types of interaction, the observed hydrogen bonds within a peptide main‐chain layer (as distinct from the side‐chain/solvent regions) cannot adapt to any of the four basic patterns observed previously for dipeptides. Instead, a rare hybrid pattern is formed.  相似文献   

17.
Dendrimers as intriguing macromolecules possess potential in phase transfer catalysis, hosts-guest chemistry, controlled release drugs or might serve as recyclable extracting agents1,2,3. The fluorine-containing dendrimers can be used as low surface-energ…  相似文献   

18.
马向霞  何锡文  张茉  李文友  张玉奎 《化学学报》2006,64(23):2369-2374
采用紫外光引发原位聚合的方法制备了具有支撑膜的扑热息痛分子印迹聚合物膜. 紫外分光光度法证明了模板分子与功能单体之间存在相互作用, 并据此选择了聚合反应时合适的溶剂. 用傅立叶红外光谱和扫描电镜分别测定了膜的结构和表面形貌. 渗透实验结果表明渗透时所用溶剂对渗透结果有重要影响. 合适的渗透溶剂可提高印迹膜对模板分子的渗透选择性.  相似文献   

19.
Ethylene is not only a substrate, but also a solvent: Catalytic intermolecular Pauson - Khand reactions of terminal alkynes were carried out in supercritical ethylene to provide 2-substituted cyclopentenones in moderate to high yields [Eq. (1)]. Under these conditions, even a low pressure of CO (5 atm) is sufficient for the reaction to take place.  相似文献   

20.
Dinuclear gold(I)-N-heterocyclic carbene complexes were developed for the hydrohydrazidation of terminal alkynes. The gold(I)-N-heterocyclic carbene complexes 2a-2b were synthesized in good yields from silver complexes synthesized in situ, which in turn were obtained from the corresponding imidazolium salts with Ag2O in dichloromethane as a solvent. The new air-stable gold(I)-NHC complexes, 2a - 2b, were characterized using NMR spectroscopy, elemental analysis, infrared, and mass spectroscopy studies. The gold(I) complex 2a was characterized using X-ray crystallography. Bis-N-heterocyclic carbene–based gold(I) complexes 2a - 2b exhibited excellent catalytic activities for hydrohydrazidation of terminal alkynes yielding acylhydrazone derivatives. The working catalytic system can be used in gram-scale synthesis. In addition, the catalytic reaction mechanism of the hydrohydrazidation of terminal alkynes by gold(I)-NHC complex was studied in detail using density functional theory.  相似文献   

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