查询词典 chiral

A HPLC method for chiral separation of citalopram hydrobromide enantiomers and optical puritydetection of escitalopram oxalate was established.

利用Chiralpak AD-H手性柱建立了氢溴酸西酞普兰对映体HPLC手性拆分的方法，同时对草酸依地普仑进行了ee值检查。

Chiral β-hydroxy acids are key intermidiates in chemical industry and organic synthesis.

手性β-羟基酸及其衍生物是应用化工和有机合成的关键中间体。

The addition reactions with phosphine anion andthe CsF promoted Strecker reactions were chose to evaluate the relationship of thesetwo chiral groups in the diastereoselective additions of the imino group.

通过亚磷酸负离子的加成反应和CsF促进下的Strecker反应研究了这两个手性基团的不对称诱导的匹配情况。

In the forth part, in the presence of chiral phosphoric acid, highly enantio-enriched (up to 98% ee)α-aryl glycine derivatives could be synthesized via asymmetric transfer hydrogenation of the α-aryl imino esters using Hantzsch ester as the hydrogen source.

第四部分工作中，利用Hantzsch酯作为氢源，高对映选择性地实现了手性磷酸催化芳基酮酸酯亚胺的不对称仿生氢化反应，以最高98％的对映选择性得到苯甘氨酸衍生物。

Xinquan HuTwo new chiral backbones R-- and S--2-amino-2"-hydroxy-4,4",6,6"-tetra methyl-1,1"-biphenyl were synthesized via nitration, diazotation/iodination, Ulhnann coupling, selective reduction, diazotation/hydrolysis, hydrogenation and resolution from 2,4-dimethyl-aniline in seven steps.

以2，4-二甲基苯胺为起始原料，经过硝化反应、重氮化碘代反应、Ullmann缩合反应、选择性双硝基单还原反应、重氮化水解反应、催化氢化反应和拆分，首次合成了--2-氨基-2'-羟基-4，4'，6，6'-四甲基-1，1'-联苯和--2-氨基-2'-羟基-4，4'，6，6'-四甲基-1，1'-联苯两个对映体。

The reaction of chiral isocyanide with N-sulfonylimine catalyzed byRh complex gave 2-imidazoline in 68 - 82% diastereoselectivity.

本论文由五部分组成·在没有任何酸，碱和催化剂存在下， N-磺酰亚胺与异氰乙酰胺反应，以60-94％的产率生成1，3-恶唑。1，3-恶唑的结构由X-ray分析测定。

Keywords: diketoreductase,isomeride,separation and purification,statins chiral side-chain expression, photoaffinity labeling probe

通过DEAE-Sepharose离子交换柱及Sephadex分子筛柱纯化后，酶的纯度达到电泳纯，并通过正相硅胶柱和反相C-18柱分离纯化其反应产物。

A series of novel aromatic amide molecular tweezers with different chiral centers and cavities were designed and synthesized by using isophthalic acid as the spacer to bridge the different L-amino acid methyl esters under microwave irradiation.

以间苯二甲酸为隔离基，酰胺键桥联L-氨基酸甲酯构成手臂，在微波辐射下合成了具有不同手性中心和裂穴的新型手性芳酰胺类分子钳。

A one-pot chemoselective reduction and lactonization of(4S,5R)-hemiesters was carried out to afford high-yielding(3aS,6aR)-lactone,a key chiral building block for the biotin synthesis. One-step introduction of carboxybutyl chain onto(3aS,6aR)-thiolactone was reached upon treatment of zinc reagent 25 in the presence of nanopalladium via an improved Fukuyama coupling under mild reaction conditions.

在侧链引入过程中，采用纳米钯LDH-Pd~0为催化剂以改进的Fukuyama偶联反应一步高效地引入-生物素五碳羧酸侧链，紧接着创造性地以离子氢化的方式建立了-生物素的第三个手性中心。

Chiral centers of C5 and C8 are directly constructed in the key step of the diastereoselective propargylation from D--tartrate. The methylation and subsequent methoxycarbonylation result in desymmetrization of the terminal dialkynes. The α,β-unsaturated δ-lactone is synthesized after partial hydrogenation and lactonization.

由非天然酒石酸出发，利用双向非对映选择性的炔丙基化反应，在一步反应中同时构建C5和C8手性中心；然后通过末端炔基的甲基化、甲酯基化，延长碳链并对分子去对称化；内酯化得到关键中间体α，β-不饱和六元内酯，再经多步反应转化得到8-epi--Boronolide。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。