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祁刚  屠树滋 《合成化学》2007,15(4):466-467,470
运用拼合原理将丙二酸酯类降糖活性化合物的药效基团丙二酸酯基与有降糖活性的香豆素拼合,设计合成3个新的了香豆素丙二酸甲酯类化合物,其结构经1H NMR,IR和MS表征。  相似文献   

3.
刘斌  解红武  马菁菁  郭雪红 《合成化学》2011,19(1):121-123,126
咖啡酸的酚羟基不作保护,直接与氯化亚砜作用生成酰氯,再与羟基香豆素类化合物完成缩合反应合成了一系列苯丙烯酸羟基香豆素酯类化合物(1a~1j),其结构经1H NMR和元素分析表征,其中1a,1c~1e为新化合物.  相似文献   

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Acylation of hydroxyl-containing heterocyclic compounds with 1,1'-ferrocenedicarbonyl chloride afforded diheteryl-1,1'-ferrocenedicarboxylates. Bisaldehyde-containing diesters were obtained by acylation of hydroxybenzaldehydes. The condensation of the latter with 2-naphthylamine or 4-phenylazoaniline resulted in the formation of the corresponding azomethines. The reduction of bisaldehyde-containing diesters furnished ferrocene-containing diols. Ferrocene tetrahydrobenzo[a]acridine-11-(7H)-one derivatives were synthesized as a result of the three-component cascade heterocyclization of ferrocene bisaldehyde-containing diesters with 2-naphthylamine and dimedone.  相似文献   

6.
Te-Butyl Telluroesters and Se-Butyl Selenoesters are hydrolyzed to carboxylic acids under very mild conditions by reaction with copper(II) chloride dihydrate. When the reaction is performed in ethanol or methanol, using anhydrous copper(II) chloride a transesterification occurred leading to the oxygenated esters in good yield.  相似文献   

7.
TEPP和OMPA都是较早发现的具有较高杀虫活性的药剂,但由于它们对温血动物毒性高而影响广泛应用[1].许多化学家发现当焦磷酸酯中P=O上的氧原子被硫原子代替,或者烧氧基被取代氨基代替,可大大降低对温血动物的毒性而仍保持其对昆虫的毒性[2,3].  相似文献   

8.
We have carried out solvolysis of the previously described ethyl esters of 3-methyl(aryl)-4-methyl-2-thioxothiazoline-5-carboxylic acids, leading to the corresponding acids without breaking down the heterocycle. We synthesized a series of novel esters from the latter by treatment with dimethyl sulfate or reactive halides. Of these, only in the case of the ethyl ester of 3,4-dimethyl-2-thioxothiazoline-5-carboxylic acid did we obtain the hydrazinolysis product (the hydrazide), from which we synthesized novel hydrazones by treatment with aldehydes and ketones.  相似文献   

9.
该文采用傅里叶变换离子回旋共振质谱(FT-ICR-MS)、核磁共振氢谱(1H NMR)以及气相色谱-质谱(GC-MS)技术,对聚甘油脂肪酸酯的结构进行鉴定。样品溶解后进行FT-ICR-MS测定,根据精确分子离子数据,推测出聚甘油脂肪酸酯的基本结构以及甘油的聚合度,并采用1H NMR进行了验证。将聚甘油脂肪酸酯水解后,对脂肪酸部分进行甲酯化,经正庚烷萃取,由GC-MS测定,分析脂肪酸的组成。综合以上结果最终确定了聚甘油脂肪酸酯的结构。该研究为聚合物的结构鉴定提供了一种新的思路和方法。  相似文献   

10.
Abstract

Aminocyclopropane phosphonic acids are considered to be “transition state analogues” of aminocyclopropanecarboxylic acids and they may serve as enzyme inhibitors1. We attempted to synthesise aminocyclopropane derivatives by a new route2. Phosphonoacetic acid allylic esters were subjected to an intramolecular, radical cyclisation in the presence of iodine, solid potassium carbonate and phase transfer catalyst.  相似文献   

11.
Parag G. Mehta 《合成通讯》2013,43(17):2497-2502
A new procedure for the synthesis of the benzylic ester of the squaric acid is described. A first example of the reaction silyl ‘enol ether’ of the squaric acid with an electrophile in the presence of a fluoride source to give an O-alkylated product is described.  相似文献   

12.
4-N-茄呢基氨基苯甲酸糖酯的合成   总被引:6,自引:0,他引:6  
赵瑾  宋金勇  王超杰 《有机化学》2003,23(7):714-716
在氢氧化钠和四丁基溴化铵存在下,将化合物4-N-茄呢基氨基苯甲酸(3) 分别与O-乙酰基溴代葡萄糖、O-乙酰基溴代半乳糖、O-乙酰基溴代乳糖和O-乙 酰基溴代麦牙糖反应制得对应的糖酯4a-4d,由元素分析,IR,~1H NMR,~(13)C NMR和MS确证了四个新化合物的结构,并做了几种抗癌生理活性测试。  相似文献   

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氨基酸卟啉锌配合物对氨基酸酯的分子识别研究(英文)   总被引:1,自引:0,他引:1  
用紫外可见吸收光谱滴定方法研究了一种新型的苏氨酸卟啉锌配合物(主体)对氨基酸酯(客体)的分子识别.这种锌卟啉可以与氨基酸酯形成 1:1和 1:2的两种加合物.氨基酸酯的氨基首先与氨基酸残基的羧基作用形成 1:1的加合物,然后与锌卟啉的中央锌原子配位形成 1:2的加合物,客体分子与主体分子上的氨基酸残基之间的排斥作用以及主客体之间的色散力作用是主体分子能识别客体分子的另外两种作用。  相似文献   

16.
Tartaric acid esters with lipophilic alcohol moieties can discriminate between enantiomeric ammonium ions such as norephedrinium ions. Quantitative results were obtained by partitioning the components between water and 1, 2-dichloroethane. The stereoselectivity was characterized by the free energy difference of the partition process (ΔΔG). Diamond-lattice sectors were used to construct models of the (unstable) lipophilic ester/ammonium salt complexes from X-ray structures of the individual components (esters and ammonium salts). These models can be used to interpret the effect of structure and configuration of the alcohol moiety on the stereoselectivity and enantioselectivity towards 1-phenyl-2-amino-1-propanol (norephedrine) salts.  相似文献   

17.
A procedure was developed for preparing esters of secondary alcohols with 7-aminoheptanoic and 8-aminooctanoic acids.  相似文献   

18.
Alkylation of 6-methyluracil, 5-hydroxy-6-methyluracil, and 6-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-ylammonium sulfate with isopropyl and ethyl chloroacetates afforded previously unknown alkyl 2-(6-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-yl)acetates, alkyl 2-(1-alkoxycarbonylmethyl-6-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-3-yl)acetates, 1,3-bis(alkoxycarbonylmethyl)-6-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-ylammonium sulfates, and alkyl 2-[1,3-bis(alkoxycarbonylmethyl)-6-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-yloxy]acetates.  相似文献   

19.
Abstract

In 1968 Zen and coworkers reported that thep-tolylsulfonyl group could be removed from carbohydrate systems by photochemical reaction (eq 1).1 Since then other investigators have used this deprotection process in carbohydrate synthesis.2-10 Mechanistic studies11-16 have shown that tosylate photolysis is promoted by compounds (e.g., triethylamine) that donate an electron to an excitedp-toluenesulfonate to generate a radical anion (1). This intermediate then fragments to form the anion of the deprotected sugar (Scheme 1). Since generating a radical anion is the central element in this photochemical process, structural changes that impact radical anion formation should influence the reaction. Replacing the p - tolylsulfonyl group with the pentafluorophenylsulfonyl group generates a more stable radical anion (2) because the electronegative fluorine atoms can help stabilize the negative charge. Since we have a continuing interest in the photochemistry of sulfonic acid esters, we synthesized the pentafluorobenzenesulfonates (pentaflates) 3-6 and studied their photochemistry under electron transfer conditions.  相似文献   

20.
A practical method for the preparation of cycloalkenyl boronic acid pinacol esters is described. These important synthetic intermediates are typically made using more expensive methods like transition metal-catalyzed borylation of alkenyl halides or triflates. In this work, they are obtained from the simple corresponding cycloalkanones, which are subjected to Shapiro reaction conditions followed by trapping with a borate ester. The requisite products are obtained in very good to excellent yields, and the reactions can be scaled up to multigram amounts. By providing a simple alternative to common methods that make use of expensive transition-metal catalysts and formation of sensitive intermediates, this convenient method will be useful for the synthesis of ring-containing partners for Suzuki–Miyaura cross-coupling and other reactions employing boronic esters as substrates.  相似文献   

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