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1.
通过酸、碱催化异构化不稳定的E-异构体,从β-苯乙醇出发,经4步反应高度立体选择性地合成了Z-脱氢氨基酸衍生物,Z-式含量可达高达99%以上。  相似文献   

2.
研究了3-芳基-4-氨基-5-巯基-1,2,4-三唑与6-/8-取代-4-羟基喹啉-3-酸在三氯氧磷催化下的反应,制得16个的3-芳基-6-(6-/8-取代-4-氯喹啉-3-基)1,2-4,-三唑[3,4-b)-1,3,4-噻二唑,新化合物的结构通过元素分析,IR,^1H NMR和MS确定,讨论了其波谱性质。  相似文献   

3.
N-芳基-5-氨基-1,2,4-三唑-3-磺酰胺的合成   总被引:3,自引:0,他引:3  
以5-氨基-3-巯基-1,2,4-三唑为原料,经氯气氧氯化后分别用邻氯苯胺和2,6-二氯苯胺胺解,合成了两个N-芳基-5-氨基-1,2,4-三唑-3-磺酰胺,产品结构经IR和1H NMR确认。  相似文献   

4.
α-酮酸、α-酮酸酯及α-酮酰胺的合成进展   总被引:1,自引:0,他引:1  
详细综述了双羰化反应和格氏试剂、草酸二乙酯一步法制备不同结构的α-酮酸、α-酮酸酯及α-酮酰胺的研究进展,参考文献23篇。  相似文献   

5.
报道了生物素全合成中的重要步骤-1,3-二苄基-4,5-顺-双羧基-2-咪唑啉酮还原为1,3-二苄基-4,5-顺-双羧甲基-2-咪唑啉酮的工艺过程,选择了几种温和的还原体系,并对它们进行了比较研究,其中体系KBH4-ZnCl2-THF的还原效果最佳。  相似文献   

6.
用1-芳基-1,4-二氢-6-甲基-4-氧哒嗪-3-酰肼与取代苯基异硫氰酸酯反应合成了系列新型取代-1,4-二氢-6-甲基-4-哒嗪酮-3-酰氨基硫脲化合物,其结构经IR,1H NMR及元素分析确认,生物活性测定表明,该类化合物对烟草花叶病毒具有很高的抑制活性。  相似文献   

7.
3-(3-吡啶基)-4-氨基-5-芳胺基-1,2,4-三唑的合成与表征   总被引:6,自引:0,他引:6  
张力学  张安将  徐志雄  张自义 《合成化学》2002,10(5):415-418,421
以烟酸与芳胺为基本原料,经多步反应,制得1-烟酰基-4-芳基氨基硫脲;后者在水合肼存在下关环,合成了一系列新化合物3-(3-吡啶基)-4-氨基-5-芳胺基-1,2,4-三唑。化合物结构经元素分析、IR,^1H NMR,^13C NMR确证。  相似文献   

8.
本文以2-氰基-4-硝基-6-溴苯胺为原料,经重氮化后与邻异丙基苯酚偶联,合成2-(2-氰基-4-硝基-6-溴苯偶氮)-6-异丙基苯酚,用乙醇重结晶精制。用元素分析,波谱等鉴定其结构,并测定其离解常数,研究该试剂的一般性质。发现其与Cu2+、Ni2+、Co2+等的显色反应在吐温80表面活性剂存在下有较高的灵敏度。  相似文献   

9.
2-氯-4-(二氯甲基)-5-羟基-2(H)-呋喃酮(MX)是饮用水氯化消毒过程中产生的一种具有强致突变性的消毒副产物(DBPs),在对MX的前驱物模拟氯化过程中,发现在MX峰的附近有一峰,有时干扰MX的测定;作者对该未知峰的质谱图进行了解析,初步推断其结构可能为2-氯-5-酮-3-烯-己二酰氯(2-chloro-5-oxo-3-hexene diacyl chloride,COHC).  相似文献   

10.
应用反相高效液相色谱法,分离和鉴定3,4,6,7,9,10-6H-3,3,6,6-四甲基-9-对硝基苯基吖啶-1,8-二酮(化合物Ⅰ),分离系统包括Zorbax SB C18及苯基柱,紫外检测器检测波长为285nm,等比和线性梯度淋洗,液相色谱-质谱联用和光导二极和列检测系统被用来鉴定主要化合物及其它杂质,此方法可达到分离效果好,灵敏度高。  相似文献   

11.
Various pyrazole and dihydropyrazolones containing an adamantane fragment were synthesized from adamantyl-substituted 1,3- and 1,4-diketones, ethyl 4-(1-adamantyl)-2-R-4-oxobutanoates (R = CN, Ac), and ethyl 2-(1-adamantylcarbonyl)-4-oxo-4-phenylbutanoate.  相似文献   

12.
《Tetrahedron: Asymmetry》1999,10(12):2327-2336
Asymmetric synthesis of 3-amino-2-hydroxy-4-phenylbutanoate, a key component of the natural product bestatin and HIV protease inhibitors of KNI-272 and R-87366, has been achieved from the stereoselective aldimine coupling reaction between 3-phenyl-2-aminopropanenitrile and (Z)-α-methoxy trimethylsilyl ketene acetal in the presence of Lewis acids.  相似文献   

13.
The reactions of methyl 2,4-dioxo-4-phenylbutanoate and methyl 2,4-dioxopentanoate with a mixture of an aromatic aldehyde and propane-1,2-diamine, depending on the initial reactant ratio, gave 4-acyl-1-(2-aminopropyl)-5-aryl-3-hydroxy-2,5-dihydro-1H-pyrrol-2-ones and 1,1′-(propane-1,2-diyl)bis(4-acetyl-3-hydroxy-5-phenyl-2,5-dihydro-1H-pyrrol-2-one). Reactions of substituted 1-(2-aminopropyl)-2,5-dihydro-1H-pyrrol-2-ones with aromatic amines and hydrazines were studied, and the structure of one of the products, 5-(2-aminopropyl)-3,4-diphenylpyrrolo[3,4-c]pyrazol-6-one, was proved by X-ray analysis.  相似文献   

14.
Investigation of the constituents of the fruits of Morus alba LINNE (Moraceae) afforded five new nortropane alkaloids (1-5) along with nor-psi-tropine (6) and six new amino acids, morusimic acids A-F (7-12). The structures of the new compounds were determined to be 2alpha,3beta-dihydroxynortropane (1), 2beta,3beta-dihydroxynortropane (2), 2alpha,3beta,6exo-trihydroxynortropane (3), 2alpha,3beta,4alpha-rihydroxynortropane (4), 3beta,6exo-dihydroxynortropane (5), (3R)-3-hydroxy-12-[(1S,4S)-4-[(1S)-1-hydroxyethyl]-pyrrolidin-1-yll-dodecanoic acid-3-O-beta-D-glucopyranoside (7), (3R)-3-hydroxy-12-[(1S,4S)-4-[(1S)-1-hydroxyethyl]-pyrrolidin-1-yll-dodecanoic acid (8), (3R)-3-hydroxy-12-1(1R,4R,5S)-4-hydroxy-5-methyl-piperidin-1-yll-dodecanoic acid-3-O-beta-D-glucopyranoside (9), (3R)-3-hydroxy-12-[(1R,4R,5S)-4-hydroxy-5-methyl-piperidin-1-yll-dodecanoic acid (10), (3R)-3-hydroxy-12-[(1R,4R,5S)-4-hydroxy-5-hydroxymethyl-piperidin-1-yl]-dodecanoic acid-3-O-beta-D-glucopyranoside (11), and (3R)-3-hydroxy-12-[(1R,4S,5S)-4-hydroxy-5-methyl-piperidin-1-yl]-dodecanoic acid (12) on the basis of spectral and chemical data.  相似文献   

15.
We have developed the chloramphenicol base urea-catalyzed intramolecular Michael addition of γ-hydroxy-α, β-unsaturated enones. The oxidation of the resulting products provided facile access to the corresponding α-hydroxy chiral alcohols with good efficiency and enantioselectivity, with the reaction displaying broad substrate scope. The utility of this methodology was further demonstrated by the synthesis of (R)-2-hydroxy-4-phenylbutanoate, which is a key building block for the construction of the ACE inhibitor benazepril hydrochloride.  相似文献   

16.
Four new pyrrolidine alkaloids, broussonetines M, O, P, and Q, were isolated from the branches of Broussonetia kazinoki SIEB, (Moraceae). Broussonetines M, O, P, and Q were formulated as (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(10S)-10,13-dihydroxy-tri decyl]pyrrolidine (1), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)9-oxo-13-hydroxy-3- tridecenyl]pyrrolidine (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(E)10-oxo-13-hydroxy-3-++ +tridecenyl]pyrrolidine (3), and (2R,3S,4R,5R)-2-hydroxymethyl-3-hydroxy-4-(beta-D-glucopyranosyloxy++ +)-5-[10-oxo-13-(beta-D-glucopyranosyloxy)tridecyl]pyrrolidine (4) respectively, by spectroscopic and chemical methods. 1-4 inhibited beta-glucosidase, beta-galactosidase and beta-mannosidase.  相似文献   

17.
Five new monoterpene glycosides, rhodiolosides A-E (1-5), were isolated from the roots of Rhodiola rosea (Crassulaceae). Their structures were elucidated as (2E,6E,4R)-4,8-dihydroxy-3,7-dimethyl-2,6-octadienyl beta-D-glucopyranoside (1), (2E,4R)-4-hydroxy-3,7-dimethyl-2,6-octadienyl alpha-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (2), (2E,4R)-4-hydroxy-3,7-dimethyl-2,6-octadienyl beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranoside (3), (2E,4R)-4,7-dihydroxy-3,7-dimethyl-2-octenyl beta-D-glucopyranoside (4), and (2E)-7-hydroxy-3,7-dimethyl-2-octenyl alpha-L-arabinopyranosyl(1-->6)-beta-D-glucopyranoside (5), on the basis of various spectroscopic analyses and chemical degradation.  相似文献   

18.
Ethyl 2-oxo-4-aryl-3-butene-1-oates 1a1c are reduced by NAD(P)H models (1-n-propyl-1,4-dihydronicotinamide (4) and Hantzsch ester(5)), in presence of magnesium perchlorate. One equivalent of the reductant reduces the substrates selectively to the corresponding 2-oxo-4-arylbutanoates (6,10a,b). An additional equivalent and higher temperature, converts ethyl 2-oxo-4-phenylbutanoate (6) to ethyl 2-hydroxy-4-phenylbutanoate (7). Reduction of ethyl 2-oxo-4-phenyl-3-buten-1-oate (1a) by Hantzsch ester in C2H5OD or by Hantzsch ester-4,4-d2 in C2H5OH, leads to direct transfer of the hydrogen or deuterium, respectively, without isotopic scrambling. These results have been interpreted to support the hydride transfer mechanism.  相似文献   

19.
( )-(4S,5R)-Osmundalactone 1 was isolated from the fungus Paxillus atrotomentosus (Paxillaceae) by Buchanan1. (-)-(4R,5S)-Osmundalactone 1 and ( )-(4R,5S)-5-hydroxy- 2-hexen-4-olide 2 were isolated from Osmunda japonica (Osmundaceae) as feeding inhibitors…  相似文献   

20.
Nine novel prenyl-dihydrofurocoumarin-type sesquiterpenoid derivatives, 2,3-dihydro-7-hydroxy-2R*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadienyl]-furo[3,2-c]coumarin, 2,3-dihydro-7-hydroxy-2S*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadien-6-onyl]-furo[3,2-c]coumarin, 2,3-dihydro-7-hydroxy-2S*,3R*-dimethyl-2-[4-methyl-5-(4-methyl-2-furyl)-3(E)-pentenyl]-furo[3,2-c]coumarin, 2,3-dihydro-7-hydroxy-2R*,3R*-dimethyl-2-[4-methyl-5- (4-methyl-2-furyl)-3(E)-pentenyl]-furo[3,2-c]coumarin, 2,3-dihydro-7-methoxy-2S*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadienyl]-furo[3,2-c]coumarin, 2,3-dihydro-7-methoxy-2R*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadienyl]-furo[3,2-c]coumarin, 2,3-dihydro-7-methoxy-2S*,3R*-dimethyl-2-[4,8-dimethyl-3(E),7-nonadien-6-onyl]-furo-[3,2-c]coumarin, and 2,3-dihydro-7-methoxy-2S*,3R*-dimethyl-2-[4-methyl-5-(4-methyl-2-furyl)-3(E)-pentenyl]-furo[3,2-c]coumarin, were isolated from the roots of Ferula ferulaeoides [corrected]. The structures were established by comprehensive spectral analysis. The biosynthetic pathway leading to these prenyl-furocoumarin-type sesquiterpenoids is proposed based on their structures.  相似文献   

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