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 共查询到19条相似文献,搜索用时 109 毫秒
1.
赵军  杨世琰 《合成化学》1996,4(1):88-90
以D-和L-酒石酸为原料,合成出高光光纯度的缩丙酮-(R)-和(S)-甘油酸(1a,1b),总收率分别为32.8和34.1%制备的关键步骤为三氯化钌与次氯酸钠对邻二醇结构中C-C键的选择性氧化断裂。  相似文献   

2.
马楠  马大为 《中国化学》2003,21(10):1356-1359
Asymmetric synthesis of irnigaine was achieved starting from an enantiopure β-amino ester 5 using the condensation of amino al-cohol 2 with acetylacetone and the subsequent intramolecular cycllzation as the key steps.  相似文献   

3.
李焰  黄锦霞  陈祖兴  方国苏 《应用化学》2001,18(10):828-830
不对称烷基化反应;莰烷磺内酰胺法合成(R)和(S)黄粉虫性引诱信息素  相似文献   

4.
黄锦霞  李焰 《应用化学》1998,15(2):79-81
(2S,3R)┐谷象虫聚集信息素的合成黄锦霞*李焰马兴泉陈祖兴徐章煌(湖北大学化学系武汉430062)关键词(2S,3R)-谷象虫聚集信息素,合成,不对称顺式醇醛缩合反应,N-莰烷-磺内酰胺1997-07-14收稿,1997-09-29修回湖北省自然...  相似文献   

5.
有机溶剂中(R)-醇腈酶催化不对称合成(R)-苯乙醇腈   总被引:3,自引:0,他引:3  
 研究了来源于杏仁的(R)-醇腈酶在有机溶剂异丙醚中催化苯甲醛与HCN不对称合成(R)-苯乙醇腈,初步探讨了来源于不同杏仁的(R)-醇腈酶的筛选、最适酶量的确定以及底物HCN与苯甲醛的配比、底物浓度、酶的微环境pH和反应温度对不对称合成反应的影响.结果发现,来源于苦杏仁的(R)-醇腈酶优于来源于甜杏仁的(R)-醇腈酶.优化的反应条件为:最适酶量150g/L,HCN与苯甲醛的配比2.5,苯甲醛浓度300mmol/L,酶的微环境pH5.4,反应温度0~5℃.在该优化反应条件下,反应平衡转化率和产物的光学纯度均高达99%以上.  相似文献   

6.
1引言烟草甲LajstodermaserricorneFabr。ins是一种主要危害烟草、香烟、干燥植物以及谷物、面粉的农业害虫。这种害虫在我国主要分布在淮河以南地区以及世界各地的温暖地带[‘]。(2,3S)-2一甲基一3一羟基成酸甲酯是我们设计的合成烟草甲性信息素的一个重要中间体。我们以丙快醇为基本原料合成了该化合物。丙炔醇参照文献l’]方法制得2一戊炔一l一醇2,催化还原条件下,炔键可被部分加氢得到(Q-2一戊烯一卜醇3。在四异丙氧基钛、D-()一酒石酸$[J4A分于筛催化条件下,顺式烯丙醇…  相似文献   

7.
合成了4种锰(Ⅲ)-苯甲酰丙酮缩乙二胺-有机碱配合物:Mn(bzacen)LClO_4.(L为哌嗪,吡啶,γ-甲基吡啶和乙腈),测定了配合物[Mn(bzacen)(CH_(3)CN)ClO_4]的结构.晶体属正交晶系.空间群P_nma.晶胞参数:a=0.9077(1)nm,b=1.5563(1)nm,c=1.7205(2)nm,V=2.4305nm ̄3,Z=4,D_c=1.48g/cm ̄3,D_m=1.49g/cm ̄3.配合物呈拉长八面体结构.对配合物的电子光谱和红外光谱进行了归属.  相似文献   

8.
从51株细菌和酵母中筛选到能够将苯甲酰丙酮(1)不对称催化还原为3-羟基-1-苯丁酮(2)的8株菌株,其中Yarrowia lipolytica CGMCC 2.150 2(A)和Trichosporon cutaneum CGMCC 2.250 0(B)具有高度的对映选择性[A还原1为(R)-(-)-2,B还原1为(S)-( )-2].A的最佳反应条件为:c(1)=30.9 mmol·L-1.c(A)=200 nag·mL-1,在1%乙醇中,pH6.5的条件下,于38℃反应20 h,(R)-(-)-2收率大于99.0%,e.e.98.7%;B的最佳反应条件为:c(1)=3.1 mmol·L-1.c(B)=200 mg·mL-1,在1%乙醇中,pH 8.0的条件下,于38℃反应36 h,(S)-( )-2收率96.2%,e.e.96.4%.  相似文献   

9.
赵培庆  宫照阳 《分子催化》1997,11(6):427-432
全过程合成出手性双膦配体2,2’-双(二苯基膦)-6,6’-二甲基联苯,以金属钌为中心原子,制备出几种不对称催化剂。通过考察不对称氢化制备(S)-(+)-萘普生的反应光学收率,研究了催化剂的催化性能,并与联萘型双膦配体催化剂进行了比较。  相似文献   

10.
γ-甲基-δ-酮己酸,γ-异丙基-δ-酮己酸在碘化N-甲基-2-氯吡啶盐存在下分别同(R)-四氢噻唑-2-硫酮-4-羧酸乙酯反应,得到光学活性的(R)-N-(γ-甲基-δ-酮己酰基)四氢噻唑-2-硫酮-4-羧酸乙酯(1a)及光学活性的(R)-N-(γ-异丙基-δ-酮己酰基)四氢噻唑-2-硫酮-4-羧酸乙酯(1b)。1a,1b分别同(R,S)-α-苯乙胺反应得到光学活性的酰胺2a,2b,同时使(R,S)-α-苯乙胺拆分,得到光学活性的α-苯乙胺。  相似文献   

11.
A simple and effective procedure for the enantioselective synthesis of (R)-and (S)-moprolol was described.The key step was the asymmetric synthesis of enantiopure (R)-and (S)-guaifenesin,which were synthesized from enantioenriched (R)-3-chloro-1,2-propanediol and (S)-epichlorohydrin via kinetics of hydrolysis resolution of racemic epichlorohydrin by chiral Salen-CoIIII complex.The e.e.values of both the optical compounds were above 98%,and the chemical structures of the target compounds were confirmed by 1H NMR,13C NMR,IR,and MS.  相似文献   

12.
Simon  H.  Vincze  Z.  Marthi  K.  Lévai  G.  Pokol  G.  Fogassy  E.  Kozma  D. 《Journal of Thermal Analysis and Calorimetry》2004,75(3):787-793
A non-isothermal experimental study using thermogravimetry (TG) and differential scanning calorimetry (DSC) was conducted for investigation the oxidation reactivity of natural phosphate and its demineralised products. The analyses were carried out in oxygen atmosphere and at different heating rate (5, 10, 20, 30, 50, 60°C min-1) up to 1000°C. The results indicated that the material washed with HCl from the original phosphate, mainly apatite and carbonates of calcium and magnesium, as well as with HCl/HF, silicates minreals, had an inhibition effect during oxidation reactions of organic material. The increase of the heating rate shifted the reactions to higher temperatures. In addition, kinetic parameters were determined by assuming a single first-order kinetic model, using the Coats-Redfern method. The influences of demineralization process of natural phosphate and the heating rate were examined and discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
(3S,4R)-Bengamide E(2) was synthesized starting from D-glucono-δ-lactone(3) and the key deoxygenation step from 13 to 15 was achieved by the application of NaBH3CN and ZnI2.Compared with natural bengamide E(1),the synthetic compound(35,4R)-bengamide E(2) was inactive against the cell growth of HUVEC and cancer cells.These data represent the significance of the stereochemistry at C-3 and C-4 of bengamides for structural recognition and binding with the target(s).  相似文献   

14.
5-(色酮基-3-次甲基)(硫代)巴比妥酸的合成   总被引:4,自引:0,他引:4  
解正峰  刘晨江  惠永海 《有机化学》2004,24(10):1278-1280
将巴比妥酸或硫代巴比妥酸、3-甲酰基色酮在乙酸-乙酸酐溶液(含乙酸酐10%)中进行缩合反应,制备了5-(色酮基-3-次甲基)(硫代)巴比妥酸.并经元素分析,IR,1H NMR及13C NMR确证了产物的结构.  相似文献   

15.
研究了一条新的路线用于他汀类药物的重要中间体(R)-4-氰基-3-羟基丁酸乙酯的合成. 以廉价、易得的L-(-)-苹果酸为起始原料, 经酯化、还原、溴代和氰化四步反应得到目标化合物(R)-4-氰基-3-羟基丁酸乙酯, 合成总收率为56.7%. 所有中间体和最终产物均由ESI-MS, 1H NMR和13C NMR光谱及比旋光度表征并与文献值比较. 该方法原料易得、操作简便、收率良好, 产物容易分离纯化, 是一条适合大规模制备(R)-4-氰基-3-羟基丁酸乙酯的新合成工艺路线.  相似文献   

16.
(+)-(1S,2S,5R)-8-联苯薄荷醇的合成   总被引:4,自引:0,他引:4  
以(R)-( )-pu legone为起始原料,经1,4-加成,还原两步反应合成了手性辅助试剂( )-(1S,2S,5R)-8-联苯薄荷醇及其差向异构体(-)-(1R,2S,5R)-8-联苯薄荷醇,总产率95%。其结构经1H NMR,13C NMR,IR,MS和X-射线衍射仪表征。  相似文献   

17.
包可婷  张伟  李英霞  胡春 《合成化学》2016,24(4):355-358
报道了一条合成(3S,4S)-4-氨基-3-羟基-5-苯基戊酸(Ahppa)衍生物的新路线。以氨基保护的L-苯丙氨酸为起始原料,依次经Weinreb胺缩合、还原、aldol缩合及溴仿4步反应合成了3个Ahppa衍生物,总收率5.8%~6.7%,其结构经1H NMR, 13C NMR和ESI-MS确证。对反应条件进行了探讨,结果表明:催化剂D-脯氨酸用量对反应收率影响不大,对立体选择性影响较大;氨基上保护基体积较大有利于提高反应立体选择性。  相似文献   

18.
(3R,5R)-3,5-二羟基-6-取代己酸不对称合成研究进展   总被引:1,自引:0,他引:1  
陈万锁  陈志荣 《有机化学》2004,24(2):140-149
概述近 2 0年来 ( 3R ,5R) 3 ,5 二羟基 6 取代己酸不对称合成进展 ,并提出其研究方向 .  相似文献   

19.
O,O'-di-p-toluoyl-(2R,3R)-tartaric acid (DPTTA) was investigated as supramolecular complex (SMC) forming resolving agent with three racemic alcohols (menthol, 4-methyl-2-pentanol, trans-2-iodo-cyclohexanol) by preparative scale experiments and thermoanalytical measurements. Despite the very small structural difference (two methyl groups) between the O,O'-dibenzoyl-(2R,3R)-tartaric acid (DBTA) and DPTTA, their SMC forming properties with water and racemic alcohols is very different. While DBTA forms SMC with all the three investigated alcohols, DPTTA forms SMC only with trans-2-iodo-cyclohexanol. DPTTA binds the guest compound less strongly and the stoichiometry of the SMC is also different. The weaker interactions resulted in less effective optical resolutions. The results of these investigations remind us, that in optical resolutions during the chiral discrimination process the weaker interactions have a determining role, since DBTA and DPTTA have the possibility to form the same strong (O-H···O and N-H···O) hydrogen bond network. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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