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In recent years, the synthesis of chiral tetrahedral clusters has been studied extensively and various types are accessible , which are a kind of organometallic compounds with greatly growing interest due to their potential application to asymmetric reaction catalysts. As an efficient 相似文献
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采用高效液相色谱法在大环糖肽抗生素键合固定相手性柱上拆分了卡巴拉汀(Rivastigmine)对映体。考察了甲醇∶乙酸∶三乙胺流动相体系中乙酸和三乙胺的浓度和比例、有机酸的种类、分离温度及流动相流速对拆分结果的影响。选定的色谱条件为:Chirobiotic V手性柱(250mm×4.6mmi.d.,5μm),流动相为V(甲醇)∶V(乙酸)∶V(三乙胺)=100∶0.02∶0.01,柱温5℃,流速0.5mL/min,检测波长274nm。在柱温5~30℃范围内测定lnα与1/T呈线性关系:lnα=ΔΔH0/RT ΔΔR0/R。 相似文献
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涂敷型手性固定相的制备及氯氟草醚乙酯对映体的高效液相分离 总被引:4,自引:0,他引:4
在前人工作的基础上,以微晶纤维素和3,5 二甲基苯基异氰酸酯为原料合成了纤维素 三(3,5 二甲基苯基氨基甲酸酯),并将其涂敷于小粒径的氨丙基化硅胶(APS)上,制备出纤维素 三(3,5 二甲基苯基氨基甲酸酯)涂敷型硅基手性固定相。通过元素分析、红外光谱对该固定相进行了表征。用正相高效液相法在该固定相上首次直接拆分了触杀型苗后除草剂氯氟草醚乙酯对映体。考察了流动相组成对对映体保留和拆分的影响,结果发现,随着异丙醇体积分数的减小,对映体的分离度逐渐增大,在异丙醇的体积分数为1 0%时,分离度已达3 95。 相似文献
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依托度酸及其中间体依托度酸甲酯的对映体分离研究 总被引:1,自引:0,他引:1
在自制的涂敷型纤维素三(3,5-二甲基苯基氨基甲酸酯)(CDMPC)和Pirlde型(S,S)-Whelk-O1两种手性柱上,对依托度酸及其中间体进行了对映体分离。考察了在流动相正己烷中,不同的醇类添加剂以及醇类添加剂的浓度对手性分离的影响,当流动相为正己烷-仲丁醇(0.39mol/L),流速1.0mL/min,温度25℃时,对映体在CDMPC柱上分离效果好。研究了溶质的体积大小及空间立体结构因素对手性分离的影响。结果发现,对(S,S)-Whelk-O1柱,溶质与固定相之问以氢键为主的吸引作用是手性识别的主要因素,而对于CDMPC柱,溶质在手性空腔中的空间适应性很可能是手性识别的关键。 相似文献
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Nikita Sarvin Ruslan Puzankov Georgii Vasiyarov Pavel N. Nesterenko Sergey M. Staroverov 《Molecules (Basel, Switzerland)》2023,28(1)
Macrocyclic glycopeptide antibiotics immobilized on silica are one of the effective classes of stationary phases for chiral recognition and HPLC separation of a wide range of optically active compounds. Enantioselectivity primarily depends on the chemical structure of the chiral ligand, immobilization chemistry, and separation conditions. In the present work, three new chiral stationary phases (CSPs) based on macrocyclic antibiotic eremomycin were prepared and investigated for enantioseparation of amino acids. Two eremomycin derivatives, including simple non-substituted amide and bulky adamantyl amide, provided important information on the role of the carboxylic group in the eremomycin structure in the chiral recognition mechanism concerning amino acid optical isomers. One more CSP having a chlorine atom in the same position elucidates the role of the first aromatic ring in the eremomycin structure as a crucial point for chiral recognition. CSP with immobilized chloreremomycin was the most successful among the phases prepared in this work. It was additionally investigated under various separation conditions, including the type and content of the organic solvent in the eluent, the effects of different additives, and the concentration and pH of the buffer. Importantly, an efficient enantioselective separation of amino acids was achieved with pure water as the eluent. 相似文献
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研究了涂敷量对双选择体手性固定相分离特性的影响。分别将纤维素-三(3,5-二甲基苯基氨基甲酸酯)与纤维素-三(4-甲基苯甲酸酯),直链淀粉-三(3,5-二甲基苯基氨基甲酸酯)与直链淀粉-三(4-甲基苯甲酸酯)进行共混,得到两种共混合物。以这两种共混合物为手性选择体,制备了涂覆量分别为17%及25%的四种手性固定相。评价了这些固定相的手性分离性能,结果表明:增加手性选择体的涂覆量,直链淀粉衍生物双选择体固定相的手性分离性能得到提高,而纤维素衍生物固定相的手性分离性能则稍有降低。较高涂覆量的纤维素衍生物固定相在含叔丁醇、异丁醇和正丁醇流动相中的保留因子依次减小,而其手性识别能力依次增强。 相似文献
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高效液相色谱手性固定相法分离取代环己酮及取代环己醇的对映体 总被引:1,自引:0,他引:1
在4种自制的涂敷型纤维素衍生物手性柱,即纤维素三苯甲酸酯(CTB)、纤维素三(4-甲基苯甲酸酯)(CTMB)、纤维素三苯基氨基甲酸酯(CTPC)和纤维素三(3,5-二甲基苯基氨基甲酸酯)(CDMPC)与小分子的Prikle型(S,S)-Whelk—O1手性柱上对取代环己酮及取代环己醇进行了对映体分离。研究了溶质的立体结构因素对手性分离的影响,并初步探讨、比较了溶质在这两种手性柱上的手性识别的机理。结果发现,在(S,S)-Whelk—O1柱上溶质与固定相之间的吸引作用是手性识别的主要原因,而对于纤维素衍生物手性柱,溶质的空间结构在手性空腔中的空间适应性可能是手性识别的关键。 相似文献
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J.F. Goossens C. Foulon C. Bailly D.C.H. Bigg J.P. Bonte C. Vaccher 《Chromatographia》2004,59(5-6):305-313
Analytical HPLC methods using derivatized cellulose and amylose chiral stationary phases were developed for the separation of the enantiomers of homocamptothecin (hCPT) derivatives which constitute a promising series of potent anticancer agents targeting DNA topoisomerase I. The resolutions were performed using a normal phase methodology with two silica-based celluloses tris-3,5-dimethylphenylcarbamate (Chiralcel OD-H) and tris-methylbenzoate (Chiralcel OJ) or two amyloses tris-3,5-dimethylphenylcarbamate (Chiralpak AD) and tris-(S)-1-phenylethylcarbamate (Chiralpak AS). The mobile phase and the chiral stationary phase were varied to achieve the best resolution. Different types and concentration of aliphatic alcohols in the mobile phase were also tested along with the temperature dependence. An optimal baseline separation (Rs > 1.5) was readily obtained in most cases. The different columns gave complementary results in term of resolution. The limits of detection and quantification were between 0.08–0.40 M and 0.24–1.80 M, respectively and the enantiomeric purity was superior to 99.9%. 相似文献
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Myung Ho Hyun Young Duk Kim Sang Cheol Han Jung Bae Lee 《Journal of separation science》1998,21(8):464-470
A chiral recognition mechanism which can rationalize the resolution of N-(3,5-dinitrobenzoyl)-α-amino amides on chiral stationary phases (CSPs) obtained from N-(3,5-dinitrobenzoyl)leucine amide derivatives has been proposed on the basis of the chromatographic resolution behavior of various N-(3,5-dinitrobenzoyl)-α-amino acid derivatives and N-(various benzoyl)leucine N-propyl amides. The proposed chiral recognition mechanism utilizes two hydrogen bonding interactions between the CSP and the analyte and a π-π donor-acceptor interaction between the N-(3,5-dinitrobenzoyl) groups of the CSP and the analyte. From the chiral recognition mechanism proposed, it has been concluded that the resolution of π-acidic N-(3,5-dinitrobenzoyl)-α-amino acid derivatives on π-acidic CSPs derived from N-(3,5-dinitrobenzoyl)leucine amide delivatives is not unusual, but is merely the extension of the resolution of the π-basic racemates on π-acidic CSPs. However, the chromatographic behavior of the resolution of N-(3,5-dinitrobenzoyl)phenylglycine derivatives on CSPs derived from N-(3,5-dinitrobenzoyl)leucine amide derivatives is different from that of the resolution of other N-(3,5-dinitrobenzoyl)-α-amino acid derivatives. To rationalize this exceptional behavior, a second chiral recognition mechanism which utilizes two hydrogen bonding interactions (which are different from those of the first chiral recognition mechanism) between the CSP and the analytes and a π-π donor-acceptor interaction between the N-(3,5-dinitrobenzoyl) group of the CSP and the phenyl group of the analytes has been proposed to compete with the first chiral recognition mechanism. In this instance, it has been proposed that the separation factors and the elution orders of the resolution of N-(3,5-dinitrobenzoyl)phenylglycine derivatives are dependent on the balance of the two competing chiral recognition mechanisms. 相似文献
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设计合成了3种源于脯氨酸的手性乙炔基单体——(S)-2-乙炔基-N-芳香胺基甲酰基吡咯烷. 在氯化降冰片二烯铑二聚体{[Rh(nbd)Cl]2}-三乙胺催化下, 3种单体被转化为相应的光学活性螺旋聚合物. 用高效液相色谱评估了3种聚合物作为手性固定相(CSPs)对9种底物的手性识别性能. 以正己烷/异丙醇(体积比9∶1)为流动相时, 3种聚合物对3对种氢键给体分子苯偶姻(α=1.35~1.44)、 三氟-1-(9-蒽基)乙醇(α=1.11~1.53)、 2,2′-二羟基-1,1′-联萘(α=1.09~1.11)及乙酰丙酮钴(α=1.84~2.38)表现出很好的手性识别能力; 当以正己烷为流动相时, 3种聚合物都能立体选择性地识别氢键给体分子2,2-二甲基-1-苯基-1-丙醇(α=1.12~1.22), 聚[(S)-2-乙炔基-N-(2′-萘基胺基甲酰基)吡咯烷]能识别氢键受体分子2-苯基环己酮(α=1.11). 结合核磁共振波谱、 拉曼光谱、 旋光测试、 紫外吸收光谱和圆二色光谱及液相色谱等方法, 系统研究了芳香侧基结构与连接位置对聚合物螺旋构象和对映体选择性拆分能力的影响. 分子对接模拟结果表明, 1-萘基的空间位阻大于2-萘基且可促进形成更强的分子内氢键, 不利于大尺寸底物(如联萘酚)的手性拆分. 与苯基相比, 引入萘基有利于增强聚合物与底物间的π-π相互作用, 提高聚合物的立体选择性和手性识别能力. 相似文献
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采用高效液相色谱法在装有大环糖肽抗生素键合相的手性柱上拆分了7种氨基带有芴甲氧羰基(fluorenylmethoxycarbonyl,Fmoc)保护的氨基酸对映体。比较了Fmoc-缬氨酸和相应的不带保护基的缬氨酸对映体在不同流动相体系中的色谱保留行为;考察了甲醇-醋酸-三乙胺流动相体系中醋酸和三乙胺的浓度以及它们二者的浓度之比对N-Fmoc氨基酸对映体拆分效果的影响。实验结果表明分离温度及流动相流速的变化也会对分离结果产生影响。该法简便快速,已成功地用于这类氨基酸的光学纯度测定。 相似文献