差向异构体

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。

Its main active component is glycyrrhizic acid. GL hastwo epimers, namelyα-GL andβ-GL.

甘草酸具有两种差向异构体，分别为α-GL和β-GL。

A baseline separation of Sitafloxacin epimers was achieved with a background electrolyte of 10 mmol/L KH2PO4-K2HPO4 (pH 4.5), 10 mmol/L CuSO4, 20 mmol/L γ-CD and 10 mmol/L D-Phe. The linear range for Sitafloxacin was 32-400 mg/L (0.996). The relative standard deviations of migration time and peak area were less than 1.9% and 3.8% respectively.

实验结果表明，添加剂的种类和浓度是影响西他沙星手性分离的重要因素，只有当D-苯丙氨酸、铜离子和γ-环糊精同时存在并达到一定浓度时，西他沙星差向异构体在毛细管电泳中才具有良好的分离效果。

Two approaches for the asymmetric syntheses of naturally occuring eudesmane-type triol kudtriol and 5-epi-kudtriol as well as their C-11 epimers were achieved starting from-dihydrocarvone through six and seven steps, respectively.

以-二氢香芹酮为原料，用两条合成路线分别经六、七步反应完成了三羟基桉烷类天然产物Kudtriol、5-epi-Kudtriol及它们的C-11位差向异构体的不对称全合成。

High performance liquid chromatography, carbon-13 nuclea magnetic resonance, chemical ionization mass spectrometry and gas chromatography with flame ionization detection have been employed for the identification and quantitative deter mlnation of the epimers of amygdalin.

登录后回答可以获得经验值奖励，并可以查看和管理所有的回答。登录|高效液相色谱法、carbon-13 nuclea 磁场共振电离质谱、化学品与气相层析法，以氢火焰离子化检测被用来识别和定量的威慑 mlnation差向异构体的苦的。

This Sm-catalyzed reaction firstly efficiently realized the catalytic cycle in the tandem rearrangement/reduction reaction of α-hydroxy epoxides, and moreover the diastereoselective amplification could be distinctly observed when two C1 epimers in substrate were subjected to this catalytic tandem reaction.

该催化的多功能串联反应，高度非对映选择性地一步控制了含有季碳的三个相邻立体中心，有效地构建了&2-季碳1，3-二醇&结构单元，首次实现了此类重排—还原过程的催化循环，其中对于两个C1位的差向异构体底物，此反应具有明显的非对映选择性放大特点。

Determination of Tyrosine in Urine Spectrophotometric Method;2. For chemical pre-extraction, MSTFA/TMSL derivatization reaction, GC/MS analysis, it is confirmed that two main metabolites (19-no-randrosterone and 19-noretiocholanolone) were found in nandrolone urine.

本文对合成的19-去甲雄烷醇酮的四个差向异构体混合物进行气相色谱分离，对诺龙和炔诺酮用药后，留取的人尿样通过化学预处理，MSTFA/TMSI衍生化反应，GC/MS分析，确证了尿样中诺龙的两个主要代谢产物为19-去甲雄酮和19-去甲原胆烷醇酮，炔诺酮的两个主要代谢物是四氢炔诺酮的两个形式，可能是3α-OH-5α-THINE和3α-OH-5β-THINE，在炔诺酮代谢前期，还发现有诺龙的上述两个代谢物存在。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。