首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
本文研究了一种新的环糊精衍生物2-O-单取代羟丙基β-环糊精做为毛细管电泳手性分离添加剂时,对3种碱性药物对映体;扑尔敏,麻黄碱,心得安的拆分性能。并与β-环糊精,2.6-O-二甲基β-环糊精,多取代2-O-羟丙基β-环糊精的手性识别性能做了对比。  相似文献   

2.
3.
研究手性化合物的分离分析方法是当今国际分析化学领域研究的热点.毛细管电泳(CE)手性分离具有高效、快速、低耗等特点,近年来已取得很大进展[‘j.环糊精(CD)及其衍生物是CE手性分离使用最多的手性选择剂,其手性分离机理是基于手性化合物(客体)的2个对映体与环糊精分子(主体)形成的包合物的稳定常数不同,而这种差别主要取决于主客体分子之间的匹配性.因此,CD及其衍生物的分子结构,包括CD衍生物的取代度和取代位,置,对手性识别有很大影响.目前,有关CD及其衍生物作为手性选择剂的CE手性分离报道较多“‘,研究的主…  相似文献   

4.
以β-环糊精、氢氧化钠和环氧丙烷为原料,通过改变原料配比合成了不同取代度的羟丙基-β-环糊精(HP--βCD).利用1H NMR对样品进行了表征,进而计算了产物的取代度.结果表明,当固定β-环糊精与氢氧化钠用量摩尔比为1∶6,且环氧丙烷用量低于18倍的β-环糊精用量时,HP--βCD的取代度随环氧丙烷用量的增加呈现规律性增加,有利于获得所需取代度的HP--βCD.  相似文献   

5.
紫外光谱法测定羟丙基-β-环糊精平均取代度   总被引:1,自引:0,他引:1  
张毅民  鲍锋  张志飞  周琴 《分析化学》2007,35(7):1055-1058
本实验以丙二醇为基准物作标准曲线,以单、双取代2-羟丙基-β-环糊精作为标准样品,建立了一种利用紫外光谱仪测定羟丙基-β-环糊精平均取代度的新方法。羟丙基-β-环糊精与浓硫酸在100℃水浴中加热反应3min,冷却后加入3%茚三酮溶液,25℃水浴中放置100min显色,用1cm比色皿于588nm处测定吸光值。通过标准曲线查出相应丙二醇的含量,换算出平均取代度。所测定的单、双取代2-羟丙基-β-环糊精平均取代度的相对误差分别为6.67%和2.81%。利用这种方法测定了在不同反应工艺条件下得到的羟丙基-β-环糊精的平均取代度,并与质谱法、核磁共振方法所测定的结果进行了比较。  相似文献   

6.
新型药物辅料2-羟丙基-β-环糊精的色谱分离纯化   总被引:1,自引:2,他引:1  
张毅民  张志飞  周琴  王拓 《分析化学》2006,34(5):713-716
利用薄层色谱方法对碱浓度为1.5%、β-环糊精∶环氧丙烷(摩尔比)=1∶21的条件下生成的2-羟丙基-β-环糊精进行了定性分析,并通过对展开剂的选择和优化,得到了3种能有效分离不同取代度2-羟丙基-β-环糊精的展开剂体系,分别为正丙醇-水-浓氨水(6∶3∶1,V/V),异丙醇-水-浓氨水(6∶4∶0.5,V/V)和乙醇-水-浓氨水(6∶3∶0.8,V/V)。通过以乙醇体系为洗脱剂的硅胶柱色谱对其进行分离纯化,得到了两种不同取代的2-羟丙基-β-环糊精。经过ESI-MS谱图分析,确定分离后产品分别为单取代和双取代2-羟丙基-β-环糊精。  相似文献   

7.
康经武  孙增培 《分析化学》1996,24(11):1273-1276
本文研究了一种新的环糊精衍生物2-O单取代羟丙基β-环糊精做为毛细管电泳手性分篱添加剂时,对3种碱性药物对映体:扑尔敏,麻黄碱,心得安的拆分性能。  相似文献   

8.
以合成的羟丙基-β-环糊精为手性选择剂,考察了HP-β-CD浓度,取代度和取代位置及缓冲溶液pH对4种碱性药物对映体的毛细管电泳分离的影响。结果表明,HP-β-CD浓度和缓冲溶液的pH是碱性药物对映体分离的重要因素,HP-β-CD的取代度和取代位置对分离有明显的影响。在选定条件下,4种试验样品达到较好的分离。  相似文献   

9.
卢铁刚  杨茂俊 《色谱》2007,25(6):830-833
建立了帕罗西汀及其中间体的高效液相色谱手性拆分分析方法。选用C18柱(4.6 mm×250 mm,5 μm),流动相为0.1%磷酸-甲醇(体积比为65∶35,含0.38 g/L羧甲基-β-环糊精,以三乙胺调pH 7.2),柱温25 ℃,检测波长210 nm。结果表明,帕罗西汀及其中间体HFP的对映异构体在30 min内同时得到了基线分离,该法与手性固定相法相比具有分离效果更好的优势。  相似文献   

10.
研究了3, 5-二甲基苯基异氰酸酯对羟丙基-β-环糊精固定相的手性识别影响.通过异氰酸丙基三乙氧基硅烷作偶联剂,将羟丙基-β-环糊精键合到3-氨丙基硅烷化硅胶上,再用3, 5-二甲基苯基异氰酸酯对β-环糊精和硅胶其余羟基进行衍生化,制得一种新型的3, 5-二甲基苯基氨基甲酸酯全衍生化羟丙基-β-环糊精键合硅胶手性固定相.在反相色谱条件下,对9种手性药物进行了拆分,结果表明,3, 5-二甲基苯基氨基全衍生化固定相较之羟丙基-β-环糊精固定相有更好的分离效果.  相似文献   

11.
This paper concentrates on the enantioseparation of racemic 2‐(substituted phenyl)propanoic acids by high‐speed countercurrent chromatography with substituted β‐cyclodextrin as the chiral selector, and an investigation of the influence of the substituent on the benzene ring in enantiorecognition between the chiral selector and enantiomer of each racemate is presented. This is an extension research of our previous work on the enantioseparation of 2‐phenyl propanoic acid derivatives, to investigate the relationship between the value of enantioseparation factor and the different substituent on the benzene ring. In total, ten racemic 2‐(substituted phenyl)propanoic acids were investigated, of which four including 2‐(4‐nitrophenyl)propanoic acid, 2‐(4‐methylphenyl)propanoic acid, 2‐(4‐hydroxyphenyl)propanoic acid, and 2‐(4‐chlorophenyl)propanoic acid, were studied by countercurrent chromatography for the first time, and two racemates were successfully enantioseparated. The distribution ratio and enantioseparation factor for all the ten racemates were determined by enantioselective liquid–liquid extraction. The results showed that an electron‐donating group on the benzene ring presents a higher enantiorecognition induced by chiral selector than that of racemates with an electron‐withdrawing group on the benzene ring.  相似文献   

12.
The synthesis of (S)-2-(3-arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)etho- xy]phenyl}propanoic acids is described. Their structures were confirmed by ^1H-NMR.  相似文献   

13.
LI  Guohua  YANG  Hong 《中国化学》2009,27(10):2055-2060
Ten methyl 2‐methoxyimino‐2‐{2‐[(substituted benzylidene)aminooxymethyl]phenyl}acetate and 2‐methoxy‐ imino‐2‐{2‐[(substituted benzylidene)aminooxymethyl]phenyl}‐N‐methylacetamide derivatives were synthesized. Structures of the new compounds were characterized by IR, 1H NMR and GC‐MS data. These compounds at 10 µg/mL were tested in vitro against five pathogenic fungi, namely, Sclerotonia, Botrytis cinerea Pers, Gibberella zeae, Rhizoctorua solani and Pyricularia oryzae. Compounds G5 , G6 , G7 and G8 showed potent antifungal activities against Botrytis cinerea Pers, G7 against Gibberella zeae and G7 , G8 against Rhizoctorua solani, respectively.  相似文献   

14.
合成了反式-1,2-双[5-(2,4,6-三甲基苯基)(口恶)唑-2-基]乙烯(1_a),并用分子力学法(MMX程序)计算了标题化合物(POEOP,2,5-二甲基-POEOP及2,4,6-三甲基POEOP).POEOP的结构、构象与X衍射结果颇吻合,分子中2个(口恶)唑环呈稳定的反向排布.比同向排布稳定4.6kJ/mol,旋转能垒约16.8~20.9 kJ/mol.还讨论了标题系列化合物的构象对其紫外光谱的影响.  相似文献   

15.
以2-氨基-5-取代苯氧甲基-1,3,4-噻二唑(1)为起始原料, 合成了中间体2-氯乙酰氨基-5-取代苯氧甲基-1,3,4-噻二唑)-2-乙酰亚胺(2)和2-(5-取代苯氧甲基-1,3,4-噻二唑-2-亚胺基)-4-噻唑啉酮(3), 化合物3进一步与取代苯甲醛发生类Knoevenagle缩合反应, 得到了一系列2-(5-取代苯氧甲基-1,3,4-噻二唑-2-亚胺基)-5-(取代苯基亚甲基)-4-噻唑啉酮类化合物4a4p. 目标化合物4a4p的结构经IR, 1H NMR和元素分析确证.  相似文献   

16.
高效液相色谱手性流动相添加法拆分阿卓乳酸对映体   总被引:1,自引:0,他引:1  
张虎  沈芒芒  童胜强  颜继忠 《色谱》2014,32(6):612-615
采用C18反相色谱柱,以磺丁基醚-β-环糊精(SBE-β-CD)作为手性流动相添加剂,建立了阿卓乳酸对映体的高效液相色谱拆分方法。考察了环糊精衍生物类型、手性添加剂浓度、流动相pH、流速和柱温对手性分离的影响,同时探讨了高效液相色谱采用磺丁基醚-β-环糊精分离阿卓乳酸对映体的分离机制及包结常数,确定了色谱条件为YMC-Pack ODS-A C18色谱柱(250 mm×4.6 mm,5 μm),流动相为含25 mmol/LSBE-β-CD的0.1 mol/L磷酸盐缓冲液(pH 2.68)-乙腈(90:10,v/v),流速为0.6 mL/min,柱温为30 ℃,紫外检测波长为220 nm。对映体的保留时间分别为26.65和28.28 min,分离度为1.68。本方法分离度好,简便易行,且比使用手性固定相分离更加经济。  相似文献   

17.
The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-1H-pyrazole-3-carboxy- late, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was characterized by X-ray diffraction, MS, NMR and IR. It belongs to the monoclinic system, space group C2/c with a = 22.723(9), b = 9.324(4), c = 18.890(8) , β = 114.259(6)°, V = 3649(3) 3, Dc = 1.272 Mg·m-3, Z = 8, Mr = 349.38, μ = 0.087 mm-1, F(000) = 1472, the final R = 0.0615 and wR = 0.1643. The biological test shows that the title compound has a moderate acrosin inhibition activity.  相似文献   

18.
The influence of different polysiloxane solvents on the efficiency and stereoselectivity of columns coated with mixtures of heptakis (2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-β-cyclodextrin and the polysiloxanes was investigated. Generally, the enantioselectivity increased with decreasing polarity of the silicone solvent and/or increasing cyclodextrin concentration, with some exceptions. Thermodynamic investigations showed that a change of the diluting phase or the cyclodextrin concentration affects entropy as well as enthalpy differences between the diastereomeric cyclodextrin/solute complexes. As a consequence, a certain cyclodextrin/polysiloxane combination is superior to another only at a particular temperature.  相似文献   

19.
Several 2-(2-chlorophenyl)-1-phenylethanones and (2-chlorophenyl)(phenyl)methanones were prepared by the Friedel-Crafts acylation reaction of 2-(2-chlorophenyl) acetic acids and 2-chlorocarboxylic acids, respectively, in the presence of cyanuric chloride, pyridine, and AlCl3 or FeCl3 using microwave heating. The yields of the ketones were significantly higher than those obtained using conventional heating. In addition, similar reactions carried out with the less inexpensive and less toxic FeCl3 gave titled ketones in comparable yields. Interestingly, the FeCl3 catalyzed reactions gave pure ketones (no chromatographic purification required), whereas the AlCl3 catalyzed reaction gave impure product that required chromatographic purification.  相似文献   

20.
韩平  刘西莉  刘鹏飞  司乃国 《分析化学》2006,34(10):1467-1470
啶菌噁唑是我国研制的一种新型农用杀菌剂。本实验建立了高效液相色谱法定量分析灰霉病菌麦角甾醇含量的方法,研究了该药剂对番茄灰霉病菌麦角甾醇合成的抑制作用。结果表明,此方法具有良好的准确度和精密度,回收率为98.8%;相对标准偏差为3.0%,适用于测定番茄灰霉病菌麦角甾醇含量;番茄灰霉病菌菌丝在不同浓度啶菌噁唑和对照药剂戊唑醇处理下,药剂对其麦角甾醇合成具有明显的抑制作用,其中在0.5、10.0mg/L啶菌噁唑作用下,菌丝麦角甾醇含量分别为1.59(±0.126)和0.10(±0.011)mg/g干重菌丝,与DMIs类杀菌剂戊唑醇处理相比,没有显著性差异;与空白对照相比,抑制率分别达到22.44%和95·12%;回归分析表明,药剂处理浓度对数与麦角甾醇含量抑制率的机率值表现出正相关线性关系。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号