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香草酸糖酯的合成研究 总被引:3,自引:0,他引:3
香草酸(4-羟基-3-甲氧基苯甲酸)广泛存在于胡黄连、高丽参、蜂胶等中药材中。它具有较强的抗氧化、抗菌活性[1,2],是良好的混合型酪氨酸酶抑制剂。闫军等通过实验证明具有C6结构且对位具有极性基团的苯酚及其衍生物是非常好的酪氨酸酶抑制剂[3],而具有C6-C3骨架的二酚及其衍生物不具有抑制酪氨酸酶的作用。B iro等[4,5]发现香草酸可诱使肥大细胞和神经胶质瘤细胞摄取钙,这与香草酸对DRG(脊髓背根神经节dorsal root ganglion)神经元的作用相似。N ish-ikawa等在对脂肪酸的糖基酯进行系统的研究中发现一些糖酯类化合物具有广泛的生物活性,… 相似文献
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以相转移催化法使α-溴代乙酰基葡萄糖,α-溴代乙酰基木糖和α-溴代乙酰基葡萄糖醛酸甲酯与5-芳基-2-呋喃甲酸在水-有机相体系中反应,合成了14个未见文献报道的糖酯类化合物,其结构经IR,HNMR,MS等证实,生物活性实验正在进行之中。 相似文献
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α-氰基乙酰甘醇酸酯是快速固化、易生物降解、韧性好的软组织粘合止血剂和瞬干胶的重要中间体。文献对其合成的报道仅有 H·Jaffe,平川栄助和. 相似文献
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糖酯类化合物具有广泛的生理活性,如抗菌、抗肿瘤等。1987年Trivedi等首次使用苯甲酰基保护的溴化α-D-葡萄糖与桂皮酸类在相转移催化剂三甲基十六烷基溴化铵的存在下反应,合成了收率为53%~82%的糖酯,此结果与Inch的结果不一致。我们在前文的基础上用2,3,4,6-四-O-乙酰基-α-D-溴代吡喃葡萄糖(1)与桂皮酸类(2~5)及与苯甲酸类(10~16),在催化剂四丁基溴化铵的存在下反应,合成了糖酯(6~9,17~23),收率为58%~82%。产品具有高度的立体选择性,~1H NMR的化学位移δ值在5.89~6.01,偶合常数J:7.2~8.1Hz,1R光谱在902.2 cm~(-1)左右具有特征吸收峰,证实为β端基异构体。 相似文献
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烷基膦酸二烷基酯的固-液相转移催化合成及其阻燃性能王筱梅*杨平蔡庆华鲍猛(山东建筑材料工业学院应用化学系济南250022)关键词烷基膦酸二烷基酯,合成,相转移催化,阻燃性1996-08-12收稿,1997-03-03修回烷基膦酸二烷基酯是一类具有实用... 相似文献
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在50%氢氧化钾溶液中,4-羟基-4'-氯二苯甲酮(1),氯仿和丙酮在相转移催化剂TEBA的催化下发生缩合反应合成了非诺贝特酸.最佳反应条件为:1 30 g,丙酮120 g,TEBA 2.5 g,氯仿40 g,于30 ℃滴加氯仿,产率89.7%. 相似文献
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We here reported on the regioselective biosynthesis of green glucosyl monoesters surfactants which were confirmed by chemical analysis methods using immobilized enzyme catalysis with N-fatty acyl amino acid and D-glucose as substrate. Lipozyme 435 was the most efficient lipase to catalyze the transesterification reaction in t-butanol at 50?°C. The target compounds showed good surface properties. The CMC values of glucosyl esters 15-22 were 4.97, 3.96, 1.87, 0.48?mmol/L, and 4.70, 3.53, 1.58 and 0.42?mmol/L at 25?°C, respectively. It was noteworthy that the micellization physiochemical parameters were calculated and the micellization was exothermic process. Meanwhile, it was entropy driven in the formation of micelles related to the structure of glucosyl esters at different temperature. 相似文献
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The coupling reaction between ethyl acetoacetate and a number of aryl halides in the presence of palladium acetate, a bulky and electron rich phosphine and K3PO4 is described. The arylated acetoacetate ester is de-acylated under the reaction conditions resulting in the generation of 2-arylacetic acid esters, constituting a mild alternative to direct arylation of carboxylate esters. 相似文献
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Diazoacetic acid cyanomethyl ester (1) was synthesized, and its chemical conversions were investigated. Catalytic denitration of compound 1 with Rh2-(OAc)4 in CH2Cl2 at 25°C in the presence of alkenes, dienes-1,3, and alkynes-1 afforded the corresponding cyclopropane- and cyclopropenecarboxylic-3 acid esters in yields of 80–85% and was almost independent of the type of unsaturated acceptor. Competitive interaction methods showed that compound 1 has a high reactivity toward terminal alkenes and alkynes, which is comparable to that of methyl and propargyl diazoacetates.For previous communication, see [1].N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 357–362, February, 1992. 相似文献
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《Acta Crystallographica. Section C, Structural Chemistry》2018,74(8):923-928
We have investigated the polymorphic phase transformations above ambient temperature for 3‐chloro‐trans‐cinnamic acid (3‐ClCA, C9H7ClO2) and a solid solution of 3‐ClCA and 3‐bromo‐trans‐cinnamic acid (3‐BrCA, C9H7BrO2). At 413 K, the γ polymorph of 3‐ClCA transforms to the β polymorph. Interestingly, the structure of the β polymorph of 3‐ClCA obtained in this transformation is different from the structure of the β polymorph of 3‐BrCA obtained in the corresponding polymorphic transformation from the γ polymorph of 3‐BrCA, even though the γ polymorphs of 3‐ClCA and 3‐BrCA are isostructural. We also report a high‐temperature phase transformation from a γ‐type structure to a β‐type structure for a solid solution of 3‐ClCA and 3‐BrCA (with a molar ratio close to 1:1). The γ polymorph of the solid solution is isostructural with the γ polymorphs of pure 3‐ClCA and pure 3‐BrCA, while the β‐type structure produced in the phase transformation is structurally similar to the β polymorph of pure 3‐BrCA. 相似文献
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F. Trotta G. Moraglio A. Rapposelli 《Journal of inclusion phenomena and macrocyclic chemistry》1994,20(4):353-361
Cyclodextrins and their derivatives act as inverse phase-transfer catalysts in the hydrolysis of carboxylic acid esters. The reaction is affected by temperature, choice of cyclodextrin and also by the stirring rate. Lipophilic esters are better hydrolyzed under inverse phase-transfer catalysis conditions than under classic phase-transfer catalysis (PTC) conditions. Some typical features of the reaction are emphasized and compared with classical PTC reactions. 相似文献