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1.
手性酰胺聚硅氧固定相的制备与气相色谱性能   总被引:2,自引:0,他引:2  
周喜春  张立峰 《分析化学》1995,23(9):1003-1008
以L-苯丙氨酸,L-缬氨酸为手性源,合成了二种含末端烯基,具有刚性苯基链节的新型手性酰胺单体;并通过硅氢加成方法将其接枝到含氢硅油上,制备了两种新型手性酰胺聚硅氧烷固定相。这一新方法具有简单易行,各步产率较高的优点,所制备了手性固定相具有较好的毛细管柱色谱性能。手性拆分能力和耐温性。  相似文献   

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利用分子烙印手性固定相串联柱同时拆分两对对映体   总被引:12,自引:1,他引:11  
采用复合功能单体制备了苯甲氧羰基-L-丝氨酸(N-Cbz-L-Ser)和苯甲氧羰基-L-丙氨酸(N-Cbz-L-Ala)烙印的分子烙印手性固定相。采用柱串联的方法,一次进样手性分离了苯甲氧羰基-DL-丝氨酸(N-Cbz-DL-Ser)和苯甲氧羰基-DL-丙氨酸(N-Cbz-DL-Ala)两对对映体,显示了分子烙印手性固定相在多对对映体同时手性分离的发展潜力。  相似文献   

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高效液相色谱手性流动相添加剂分离肾上腺素类对映体   总被引:21,自引:2,他引:19  
李桦  胡先明  谢颖峰 《色谱》1998,16(5):424-426
将β-环糊精、2,6-二甲基-β-环糊精、2,3,6-三甲基-β-环糊精分别作为手性流动相添加剂,较系统地研究了D,L-肾上腺素、D,L-异丙肾上腺素、D,L-麻黄碱在反相HPLC系统中的拆分,建立了甲基化β-环糊精动态手性固定相法分离肾上腺素类药物对映体的方法,探讨了立体选择性与环糊精主体和客体分子结构之间的关系  相似文献   

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合成了用于气相色谱(GC)的手性衍生化试剂N-七氟丁酰基-L-脯氨酰氯(N-HFB-L-PCl)。各种特性试验表明,N-HFB-L-PCl是灵敏的GC手性衍生化试剂,可直接于水相拆分微量的手性胺对映体。  相似文献   

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曾苏 《色谱》1994,12(5):358-360
 合成了用于气相色谱(GC)的手性衍生化试剂N-七氟丁酰基-L-脯氨酰氯(N-HFB-L-PCl)。各种特性试验表明,N-HFB-L-PCl是灵敏的GC手性衍生化试剂,可直接于水相拆分微量的手性胺对映体。  相似文献   

6.
对映体选择性配体交换膜的制备和DL-氨基酸的拆分   总被引:8,自引:0,他引:8  
龙远德  黄天宝 《合成化学》2000,8(4):317-320
制备了一种新型光学分离膜,即带有L-脯氨酸手性选择子的交联聚乙烯醇膜,考察了DL-酪氨酸,DL-苯丙氨酸和DL-色氨酸通过膜的对映体选择性渗透性能。发现L-氨基酸优先透过膜,消旋氨基酸透过膜的对映体拆分机理类似于手性配体交换色谱方法拆分消旋氨基酸的机理,在DL-氨基酸的对映体选择性膜透过中,对映体选择性吸附着重要的作用。  相似文献   

7.
李关宾  林秀丽  主沉浮  吴培  关亚风 《分析化学》2000,28(10):1287-1290
以L-谷氨酰胺为手性选择剂,建立了对普萘洛尔、慢心律、心律平、苯丙哌酮、异丙肾上腺素、氯胺酮、山莨菪碱、洛贝林、布比卡因、苯海索等10种手性药物对映体的毛细管电泳快速分离方法,在含有60mmol/L L-谷氨酰胺,60mmol/L硼砂(pH=9.25)的缓冲溶液中,10种手性药物在11min内达到基线分离。并对分离机理作了初步探讨。  相似文献   

8.
以焦谷氨酸为原料,通过两种路线,分别合成了5-位反式苯基取代脯氨酸和5-位顺式苯基取代脯氨酸,总收率分别为43.9%和51.0%。其结构经1H NMR,13C NMR和MS表征。  相似文献   

9.
质谱中的立体化学效应(ⅩⅤⅢ)──用反应质谱法检测α-氨基酸的手性潘远江,翟建军,陈耀祖(兰州大学化学系,兰州大学分析测试中心,兰州,730000)关键词反应质谱,α-氨基酸,手性检测前文[1]我们用D-及L-苦杏仁酸作为反应试剂通过化学电离质谱区分...  相似文献   

10.
毛细管电泳分离与测定尿液中扑尔敏对映体   总被引:2,自引:0,他引:2  
以HP-β-CD作为手性分离添加剂,对标样和实际尿液中的扑尔敏进行了手性分离和测定研究。在实际样品的分离测定时,用液液萃取时间样品预处理,并采用电堆集进样以提高检测灵敏度,对于尿液中扑尔敏对映体的检测限为1.5×10^-7g/L。  相似文献   

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HEPT类化合物的QSAR研究   总被引:3,自引:0,他引:3  
章文军  许禄 《应用化学》2001,18(9):717-0
为定量结构/活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法(Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物(1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构/活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。  相似文献   

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The dependence of the chemical shifts of the ring protons on the pH of the medium for a number of 4-hydroxyquinoline derivatives was studied by means of PMR spectroscopy. The dipolar and uncharged hydroxy forms exist in equilibrium in aqueous solutions. The effect of intramolecular hydrogen bonding on the character of the dependence of the chemical shift on the pH of the medium in the case of 3-piperidinomethyl-4-hydroxyisoquinoline was investigated. The possibility of the separate protonation of the ring nitrogen and the side-chain nitrogen in 3-piperidinomethyl-4-hydroxyisoquinoline was established. The distribution of the -electron density in 4-hydroxyisoquinoline is in good agreement with its chemical behavior.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1549, November, 1971  相似文献   

16.
The dependence of the chemical shift of the ring protons on the pH of the medium for a number of 3-hydroxyquinoline derivatives was studied by PMR spectroscopy. The regions of ionization of the molecules, which correspond to the ranges of acidic, neutral, and alkaline media, were found. In D2O, 3-hydroxyquinoline is present only in the uncharged hydroxy form. The presence of intramolecular hydrogen bonding in 4-dimethylaminomethyl-3-hydroxyquinoline has a substantial effect on the character of the dependence of the chemical shift on the pH of the medium; the existence of separate protonation of the nitrogen atoms of the ring and the side chain of 4-dimethylaminomethyl-3-hydroxyquinoline was established. The distribution of the -electron density in the 3-hydroxyquinoline molecule is in good agreement with its chemical behavior during electrophilic substitution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1540–1545, November, 1971.  相似文献   

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Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.  相似文献   

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