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合成了纤维素-三和纤维素-三衍生物,并涂敷于自制的球形硅胶上,制备了用于高效液相色谱手性拆分的固定相。考察了涂敷量,流动相等因素对对手性拆分的影响,测定了一个不对称氢化酯化反应的对映体过剩值。 相似文献
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将三(苯基氨基甲酸)支链淀粉酯涂敷在硅胶上制成了手性固定相.将支链淀粉与过量的苯异氰酸酯在吡啶中反应得到的苯基氨基甲酸酯溶解并涂敷在用3-氨基丙基三乙氧基硅烷处理过的硅胶上,涂敷量为0.45/2.55(重量比).用此手性固定相拆分了外消旋的簇合物μ-FcCCHCoW(CO)5(CpCOOC2H5).拆分在室温下进行,洗脱液为甲醇,流速为0.5mL/min. 相似文献
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将三(苯基氨基甲酸)支链淀粉酯涂敷在硅胶上制成了手性固定相,将支链淀粉与过量的苯异氰酸酯在吡啶中反应得到的苯基氨基甲酸酯溶液并涂敷在用3-氨基丙基三乙氧基硅烷处理过的硅胶上,涂敷量为0.45/2.55重量比,用此手性固定相拆分子外消旋的簇合物μ-FcC=CHCoW(CO)5(CpCOOC2H5),拆分在室温下进行,洗脱液为甲醇,流速为0.5mL/min。 相似文献
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制备并表征了纤维素-三(苯基氨基甲酸酯)涂敷氧化锆手性固定相,并用该固定相直接拆分了3种硒代缩水甘油醚。考察了固定相涂敷量、流动相组成等对手性拆分的影响。讨论了硒代缩水甘油醚分子结构与保留因子、选择性因子和分离因子的关系。结果表明,固定相的羰基和氨基是手性分离的主要部位,固定相的手性空穴是对映体分离产生立体差异的关键,对映体手性碳上连接的基团的立体效应是影响拆分的主要因素。实验结果表明:纤维素-三(苯基氨基甲酸酯)是性能稳定、有很好的手性拆分能力的固定相。 相似文献
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几种手性化合物在纤维素衍生物涂敷的SBA-15手性固定相上的直接拆分 总被引:1,自引:0,他引:1
以三嵌段聚醚P123为模板, 四乙氧基硅烷为前驱体, 在强酸性条件下合成了高比表面积、大孔径、微米级的球形SBA-15. 将纤维素-三(3,5-二甲基苯基氨基甲酸酯)(CDMPC)涂敷在氨丙基化的SBA-15微球上, 作为手性固定相, 在正相条件下直接拆分了七种不同类型的手性化合物. 实验发现, 与同样尺寸的CDMPC涂敷的氨丙基硅胶手性柱相比, 手性化合物在所制备的新型手性固定相上有较强的保留、具有较高的分离因子|新制备的手性固定相不仅有较好的渗透性, 而且具有较高的手性识别能力. 因此, 高比表面的介孔SBA-15微球适合作为手性色谱填料基质. 相似文献
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Summary The enantiomeric separation of nineteen biphenyl dimethyl dicarboxylate derivatives has been examined by HPLC on a chiral
statonary phase prepared by coating aminopropylated silica gel with cellulose tris-(3,5-dimethylphenylcarbamate). It was found
that trifluoroacetic acid (TFA) has a dominant effect on chiral separation for acidic compounds. The percentage of 2-propanol
in the mobile phase does not have a large effect on the anantioselectivity but the separation was dramatically influenced
by the kind of alcohol in the mobile phase. The effect of temperature on the chiral separation is also discussed. Most of
the enantiomers investigated could be resolved satisfactorily. 相似文献
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无机介孔硅球因其具有足够的机械强度、热稳定性,以及适应多种流动相的优点,成为高效液相色谱(HPLC)柱填料中使用最广泛和最重要的材料。但在此研究领域中,并未见球形的全无机手性硅胶用作HPLC手性固定相。该文以无机球形介孔硅胶作为研究对象,通过堆砌硅珠法,以硅溶胶为原料,L-谷氨酸(L-Glu)为手性源,在手性环境中制造出脲醛树脂与胶体二氧化硅混合的小球,在550 ℃高温下煅烧除去树脂部分,制备基于L-Glu的无机介孔硅胶球。通过元素分析、红外光谱、扫描电镜、透射电镜和氮气吸附等表征证明这是一种具有规则球形的手性硅胶球,其手性来源于硅胶球自身的骨架和孔结构。将L-Glu手性硅胶球作为固定相制备了HPLC色谱柱,以正己烷-异丙醇(9∶1, v/v)作为流动相,流速为0.1 mL/min,考察了该手性柱对一系列外消旋化合物的拆分性能。实验表明,该手性柱拆分了15种外消旋化合物,其中特罗格尔碱、吡喹酮、3-苄氧基-1,2-丙二醇、1,2-环氧己烷、3-羟基-2-丁酮、2-甲基四氢呋喃-3-酮、异丙基缩水甘油醚达到基线分离;还分离了10种苯系位置异构体,o,m,p-氨基苯酚、o,p-氯苯酚、o,m,p-碘苯胺、o,m,p-甲苯胺、o,m,p-二硝基苯、o,m,p-氯苯胺、o,m,p-硝基苯酚、o,m,p-溴苯胺达到基线分离。实验表明,L-Glu手性硅胶球在手性分离方面具有良好的可行性,与普通硅胶相比不需要进一步修饰就可以有较好的手性分离效果,是一种低成本、制备便捷的手性无机硅胶固定相。 相似文献
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表层纳米氧化锆包覆硅球色谱载体的制备和表征 总被引:2,自引:0,他引:2
硅胶是目前应用最为广泛的色谱载体. 硅胶的比表面积及孔体积大, 渗透性好, 孔结构适宜于色谱分离, 但在pH<2及pH>8条件下不稳定, 对碱性化合物, 尤其是对生物样品产生不可逆吸附. 氧化锆化学性质非常稳定[1], 适宜碱性样品尤其是生物大分子的分离; 但是其比表面积和孔体积小[2~5], 孔结构对色谱分离不利[6], 可涂敷的固定相量较小, 渗透性差. 本文采用分子自组装方法[7~9]在微米硅球表面包覆多层纳米氧化锆制备了较为理想的色谱载体. 相似文献
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Sang Hyun Kwon Yoshio Okamoto Chiyo Yamamoto Wonjo Cheong Myeonghee Moon Jung Hag Park 《Analytical sciences》2006,22(12):1525-1529
Porous zirconia particles are very robust material and have received considerable attention as a stationary phase support for HPLC. We prepared cellulose dimethylphenylcarbamate-bonded carbon-clad zirconia (CDMPCCZ) as a chiral stationary phase (CSP) for separation of enantiomers of a set of 14 racemic compounds in normal phase (NP) and reversed-phase (RP) liquid chromatography. Retention and enantioselectivity on CDMPCCZ were compared to those on CDMPC-coated zirconia (CDMPCZ) to see how the change in immobilization method of the chiral selector affects the retention and chiral selectivity. In NPLC, retention was longer and the number of resolved racemates was smaller on CDMPCCZ than on CDMPCZ. However, chiral selectivity factors for some resolved racemates were better on CDMPCCZ than on CDMPCZ. The longer retention on CDMPCCZ is likely due to strong, non-chiral discriminating interactions with the carbon layer on CDMPCZ. In RPLC only two racemates were resolved on CDMPCCZ, but retention times were shorter than, and resolutions were comparable to, those in NPLC, indicating a potential for improving chromatographic performance of the CDMPCCZ column in RPLC with optimized column preparation and separation conditions. 相似文献
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Bromoacetate‐substituted [3‐(2‐O‐β‐cyclodextrin)‐2‐hydroxypropoxy]propylsilyl‐appended silica particles (BACD‐HPS), an important and useful synthetic intermediate for preparation of novel types of macrocycles‐capped β‐CD‐bonded silica particles including crown ether/cyclam/calix[4]arene‐capped β‐CD‐bonded silica particles, have been prepared and used as chiral stationary phase for HPLC. This synthetic stationary phase is characterized by means of elemental analysis. For the first time, the chromatographic behavior of BACD‐HPS was systematically evaluated with several disubstituted benzenes and some chiral drug compounds under both normal and RP conditions in HPLC. The results show that BACD‐HPS has excellent selectivity for the separation of aromatic positional isomers and chiral isomers of some drug compounds when used as stationary phase in HPLC. 相似文献
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合成了纤维素-三(苯甲酯)(CTB)和纤维素-三(氨基苯甲酸酯)(CTPC)衍生物,并涂敷于自制的球形硅胶上(5μm,13nm),制备了用于高效液相色谱手性拆分的固定相.考察了涂敷量、流动相等因素对手性拆分的影响,测定了一个不对称氢化酯化反应的对映体过剩值(e.e.值). 相似文献
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Two novel chiral stationary phases (CSPs) were prepared based upon the regioselective immobilizations of beta-cyclodextrin (beta-CD) at its C2 position to the silica support. The mono-2A-azido-2A-deoxyperphenylcarbamoylated beta-cyclodextrin and mono-2A-azido-2A-deoxyperacetylated beta-cyclodextrin were synthesized by selective tosylation and azidolysis followed by perfunctionalisation. The derivatised cyclodextrins were then immobilized onto the aminised silica gel via the Staudinger reaction to provide new chiral stationary phases. Their application to high-performance liquid chromatography (HPLC) enantioseparation of racemic compounds was demonstrated using beta-adrenergic blockers, flavonone compounds, benzodiazepinones, antihistamines and weakly protolytic compounds, of which good separations were achieved for some racemic compounds, for instance, bendroflumethiazide (Rs 6.26), oxazepam (Rs 5.99), temazepam (Rs 2.85) and althiazide (Rs 1.13) when compared with the corresponding CSPs where the beta-CD molecule was regioselectively immobilized at the C6 position. The enantiodiscriminatory properties of these CSPs were found to be affected by the orientation of the CD cavity under reversed-phase conditions, and also by the derivitising groups of the CD. The HPLC results inferred that the mono-6A-azido-6A-deoxyperphenylcarbamoylated CD CSP (CD bonded at C6 position to silica) exhibited slightly better chiral recognition ability than mono-2A-azido-2A-deoxyperphenylcarbamoylated CD CSP under the normal-phase and reversed-phase modes on the separation of 31 different racemic compounds and drugs. On the contrary, higher chiral recognition abilities were observed on the mono-2(A)-azido-2A-deoxyperacetylated CD CSP compared to mono-6A-azido-6A-deoxyperacetylated CD CSP. 相似文献