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3A series of C_2-symmetric chiralβ-amino alcoholsⅢ-6 andⅢ-10were synthesized in several steps from natural amino acids,and applied in the asymmetric borane reduction of prochiral ketones.The catalytic activity ofⅢ-6 was better thanⅢ-10.

3以天然氨基酸为起始原料，经过简单的几步反应合成了开链冠醚类C_2-对称的手性β-氨基醇Ⅲ-6以及Ⅲ-10，将其应用于硼烷对前手性酮的不对称还原反应中，含有脯氨醇结构单元Ⅲ-6的催化效果要好于由其他氨基酸衍生的Ⅲ-10，THF为溶剂，回流，催化量为10 mol%时，最高得到85%的ee值。

Oxazaborolidine, which derive from the coordination of amino alcohol and borane, are good catalysts for the borane reduction reaction. A kind of fused cyclic oxazaborolidine invented by Corey and derived from proline has been successfully used in the production of MK-0417 as excellent chiral catalyst by Merck company.

在该反应中氨基醇类配体原位与硼烷配位形成的手性恶唑硼烷是该反应的良好催化剂，其中Corey等发明的由脯氨酸出发制备的稠环手性催化剂性能优异，已经在Merck公司生产碳酸酐酶抑制剂MK-0417中得到成功应用。

S-1-phenylethanol was obtained in up to 19%ee in toluene at 0℃.(4)A series of C_2-symmetric chiralβ-amino alcoholsⅣ-5were synthesized in several steps from natural amino acid L-proline,and applied in the asymmetric borane reduction of prochiral ketones.

4以天然L-脯氨酸为起始原料，经过几步转化合成了以萘环为母体的C_2-对称的手性β-氨基醇Ⅳ-5，将其应用于硼烷对前手性酮的不对称还原反应中，同样，我们也观测到温度影(来源：Ac1BC论文网www.abclunwen.com)响产物构型的现象。

Asymmetric catalytic activity of chiral spiroborate esters,- or-1,1′-bi-2-naphthoxyboric acid-proline anhydride [-1 or-1], toward borane reduction of prochiral imine s has been ob- served.

手性螺硼酸酯-或-1，1'-联-2-萘酚硼酸--脯氨酸酐[-1或-1]对前手性亚胺硼烷还原的不对称催化活性被观察到。

Thirty-one new chiral phosphorus compounds have been synthesized starting from D-camphor,-alpha-phenylethylamine,-Betti base,-1-(4-nitrophenyl)-2-amino- propane-1,3-diol, L-amino acids (such as serine, phenylalanine, proline etc.) and their application as organocatalysts in asymmetric trimethylsilylcyanation of aldehydes and asymmetric borane reduction of prochiral ketones and ketimines were investigated.

该项目从D-樟脑、-alpha-苯乙胺、-Betti碱、-氯酶胺、L-氨基酸（如丝氨酸、苯丙氨酸、脯氨酸等）出发合成了31个新的手性磷化合物，研究了它们作为有机催化剂在醛的不对称硅氰化反应、潜手性酮的不对称硼烷还原反应以及亚胺的不对称硼烷还原反应中的催化效果。

The application of perfluoroalkanesulfinyl chlorides and chiral perfluoroalkanesulfinamines in organic synthesis was studied in this dissertation.

中文摘要本论文对全氟烷基亚磺酰氯在含氟化合物合成中的应用进行了研究，并对它的衍生物手性全氟烷基亚磺酰胺的制备和应用进行了初步探索。

Separation of racemic mixtures of benzyl glycidyl ether was achieved with HPLC by using Chiralcel OD as chiral stationary phase and hexane/2-propanol mixture of different ratios as eluents.

在 Chiralcel OD多糖类手性固定相上，以各种不同配比的正己烷-异丙醇为洗脱剂，对苄基缩水甘油醚的外消旋体进行对映体拆分，考察了不同洗脱剂配比、柱温和流速对分离度和出峰时间的影响。

Separation of racemic mixtures of thirty-eight secondary aromatic alcohols and arylethanediols with different substituting group was achieved with HPLC by using Chiralcel OD and Chiralcel LJ as chiral stationary phase and hexane/2-propanol mixtures of different ratios as eluents. The chromatographic parameters of these racemates on OD and OJ columns were examined.

在ChiralcelOD和ChiralcelOJ两支多糖类手性固定相上，以各种不同配比的正己烷-异丙醇为洗脱剂对38种带有不同取代基的芳香仲醇及芳香乙二醇类手性化合物的对映体进行拆分，考察了这些外消旋体在这两支手性柱上的色谱行为。

Sitafloxacin epimers were separated by capillary zone electrophoresis using γ-cyclodextrin and D-phenylalanine as chiral selector.

以γ-环糊精和D-苯丙氨酸为手性选择剂，采用毛细管区带电泳成功地分离了新型抗菌素西他沙星差向异构体。

Enantiopure epoxides are versatile chiral building-blocks in organic synthesis and can be used for convenient synthesis of many bioactive compounds.

手性环氧化物是有机合成中非常重要的手性合成砌块，可以方便地合成许多有生物活性的手性化合物，因而在手性合成和医药工业上具有极其重要的应用价值。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。