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The first asymmetric synthesis of trans-β-hydroxy-γ-butyrolactones:-(3R, 4R, 5S)-4-(1-acetoxy-isopropyl)-3-hydroxy-butyrolactone 65a was achieved starting from isobutylaldehyde through nine steps. The key steps involve the construction of three chiral carbon centers by the Sharpless's asymmetric epoxidation and Substrate directable chemical reaction.

以异丁醛为起始原料，经过九步反应首次设计合成了具有三个手性中心的trans-β-羟基-γ-丁内酯：-（3R，4〓，5S）-4-（1-乙酰氧基-异丙基）-3-羟基-丁内酯65a，关键步骤是Sharpless不对称环氧化和底物定向不对称合成反应。

B. Three novel dimeric dissymmetric chiral ligands and six chain binuclear Salen complexes were synthesized and characterized by FT-IR,〓HNMR, Elemental analyses, UV-vis, furthermore the CD spectra properties of the ligands and complexes were discussed in detail for the first time.

合成了三个未见报道的链式双Salen配体和六个链式双核Salen金属配合物，通过核磁共振波谱、元素分析、红外光谱、紫外-可见光谱进行了表征，并首次详讨论了手性配体及配合物的圆二色光谱性质。

for preparing n-boc or n-cbz derivatives of chiral alpha,alpha'-disubstituted pyrrolidines containing olefinic bond and acetylene bond

一种制备含烯键和炔键取代基的手性α，α'-二取代吡咯烷的n-boc或n-cbz衍生物的方法

The dyadic Green's functions are important tools for solving the electromagnetic boundary value problems of chiral media .

旋波媒质中电磁波的传播理论及其在工程中的应用研究是电磁理论重点研究的课题之一。

Quantum chemical calculations were performed based on these conformations to explain the experimental data. 4. The molecular recognition of the chiral Salen Fe complexes towards imidazole derivatives and the measure of the equilibrium constants of host-guest system of the Salen Fe and EMIm a.

用紫外-可见光谱滴定法考察了不同主体Salen-Fe对咪唑及其衍生物的分子识别行为，测定了识别过程的平衡常数和热力学参数，讨论了影响主客体配位能力的有关因素；系统地考察了主客体缔合反应的圆二色光谱性质。

Subsequently,enol methylation of P in basic condition completed the synthesis of malyngamide O.Applied this route to the synthesis of malyngamides Q and R,the chiral unsaturated acid was connected with the vinyl chloride part by amidation,then the resulting product was converted into the corresponding aldehyde,followed by aldol condensation of the aldehyde with the chlorotitanium enolate of pyrrolidone to complete the skeleton of malyngamides Q and R,then the synthesis of them was completed via enol methylation in acid condition.

该合成路线拓展应用到malyngamides Q和R的合成时，首先用酰胺键将手性不饱和脂肪酸和烯氯片段连接，再转化成相应的醛，与乙酰基吡咯酮进行TiCl_4催化的aldol反应即得到malyngamides Q和R的骨架结构，再经过酸催化的烯醇甲基化反应完成了Q和R的全合成。

Study on Asymmetric Cyclopropanation of 2,5 Dimethyl 2,4 hexadiene Catalyzed by Chiral Copper Complexes

说明：补充资料仅用于学习参考，请勿用于其它任何用途。

Then the protected D-mannitol, mixed with lead tetraacetate, hippuric and acetic anhydride, were refluxed in THF for 18 h in a one-pot two step reaction to afford a chiral precursor-2-phenyl-4-[-2,3-O-]-propylidene-5(4H)-oxazolones.

产物与四乙酸铅、马尿酸、乙酐于THF中回流18 h完成一釜二步反应，纯化后得到含有手性碳原子的环丙烷氨基酸前体-2 苯基-4-[-2，3-O-]丙叉？

Different from the conventional catalyst immobilization methods, the self-supporting strategy utilizes homochiral metal-organic coordination polymers generated by self-assembly of chiral multitopic ligands with metal ions without using any support.

与传统的负载模式不同，手性自负载催化剂通过含双或多官能团的手性配体与金属通过自组装形成一类有机-无机聚合物，因此无需使用任何载体，即能够有效地实现手性催化剂的回收和再利用。

Resolution of benzoin,hydrobenzoin and α- phenethyl alcohol with-phenylglycine based chiral stationary phase(Chirex 3001)in the normal-phase conditions were studied.

正相模式下研究了安息香、氢化安息香及α-苯乙醇在苯基甘氨酸型手性固定相Ch irex 3001上的拆分，探讨了流动相组成及柱温对手性拆分效果的影响。

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％。