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1.
环糊精在有机合成中的应用   总被引:13,自引:0,他引:13  
黄乃聚  尤晨  章道道 《有机化学》1987,7(6):482-488
环糊精(cyclodextrin,CD)是环状低聚糖的总称。由6个、7个或8个葡萄糖单元以1,4-糖苷键结合而成的环糊精分别称为α-,β-和Υ-环糊精(简写为α-CD,β-CD 或Υ-CD)。它们的分子形状都是略呈锥形的圆环。例如,β-CD 有如下结构。由于环中的各个葡萄糖单元皆处于椅式构  相似文献   

2.
制备了对苯二甲酸连接的环糊精二聚体(α,α-CD Dimer)及紫精聚合物(VP),利用α,α-CD Dimer与VP之间的主客体识别作用构筑了一种超分子水凝胶.1H NMR测定结果表明α,α-CD Dimer和VP的主客体相互作用是通过α-CD空腔和VP形成包结络合物进行的.环糊精二聚体α,α-CD Dimer和聚合物VP凝胶体系的构筑受环糊精二聚体类型的影响,同时该超分子水凝胶对有竞争作用的客体分子表现出响应性,该超分子水凝胶在竞争性客体分子存在的条件下,可发生小分子诱导的凝胶与溶胶转化行为.此外,该凝胶体系还具有良好的热稳定性.  相似文献   

3.
环糊精毛细管气相色谱柱对某些芳香族化合物的分离作用   总被引:1,自引:1,他引:0  
陆懋荪  于东海  阎长泰 《色谱》1989,7(1):33-35
环糊精(以下用CD代表)是由多个葡萄糖单元经α-1,4联结而成的一系列环状低聚糖,当萄葡糖基分别为6和7个时,各称为α-CD和β-CD。CD具有独特的分子结构可与多种化合物形成稳定性各异的包含复合物,因而用CD及其衍生物作为气相色谱固定相表现出特殊的选择性分离作用。现有文献报道的工作均是在填充柱上进行的,其峰形和柱效尚不够理想,考虑到毛细管气相色谱的优点,本文用α-CD和β-CD的甲酰胺或乙二醇溶液作为毛细管柱的固定  相似文献   

4.
以β-环糊精修饰的壳聚糖(CDCS)和二茂铁修饰的聚乙二醇(FCPEG)为构筑单元,以伊环糊精和二茂铁的主客体相互作用为驱动,构筑了水溶性的超分子聚合物CDCS-FCPEG。在此基础上,加入α-环糊精(α-CD),通过其对聚乙二醇的穿环络合诱导结晶作用,制备了壳聚糖基水凝胶。使用核磁(^1H—NMR)、紫外一可见光谱法(UV—Vis)、X射线衍射分析(XRD)和循环伏安法(CV)等手段进行了验证。结果表明:超分子聚合物CDCS—FCPEG与共价键连接的传统聚合物一样可以和α—CD形成凝胶。  相似文献   

5.
薄涛  杨学东  贡素萱  李克安  刘虎威 《色谱》2003,21(6):535-540
 研究了毛细管区带电泳分离中以β-环糊精(β-CD)和磺酸化β-CD为添加剂时10个山酮类化合物电泳行为的差异,并用毛细管电泳求得β-CD 和磺酸化β-CD与山酮类化合物间的结合常数。在分子动力学基础上,运用计算机技术模拟了β-CD 、磺酸化β-CD与山酮类化合物的包合过程,从而求得主客体间的相互作用能。同时,运用量子化学计算了山酮分子的物化参数,并选择相互作用能(INE)、疏水常数(log P;其中P为正辛醇-水分配系数)和山酮分子总能量(TE)作为分析结构-电泳迁移定量关系的物化参数,用以研究分离机制及  相似文献   

6.
制备了侧链含α-环糊精(α-CD)的聚丙烯酸(PAA-α-CD)作为主体聚合物,侧链含偶氮基团(Azo)的聚丙烯酰胺(PAM-Azo)作为客体聚合物.利用1H NMR、2D NOESY NMR方法测定了PAA-α-CD与PAM-Azo间的主客体作用.结果表明,PAM-Azo侧链的trans-Azo基团能够被PAA-α-CD侧链的α-CD包结,而cis-Azo基团不能被α-CD包结.在一定浓度下,PAA-α-CD与PAM-Azo通过主客体间的识别能够形成超分子水凝胶,并且该凝胶具有光响应性.在365nm紫外光光照下,PAM-Azo侧链的trans-Azo转变为cis-Azo,不能被PAA-α-CD侧链的α-CD包结,超分子水凝胶转变为溶胶.而在430nm的可见光光照下,PAM-Azo侧链的cis-Azo转变为trans-Azo,重新被PAA-α-CD侧链的α-CD包结,又可得到超分子水凝胶.  相似文献   

7.
本文合成了两种含有三蝶烯单元的分子钳1和2,通过1H NMR、13C NMR、质谱、元素分析以及X射线单晶衍射等手段确证了化合物的结构。通过核磁滴定法以及ESI-MS法研究了化合物1和2在溶液中与7种缺电子客体的络合行为,结果表明:1)主客体之间的络合是按照摩尔比1∶1进行的;2)两种主体的配位能力12;3)缺电子程度大的客体与主体络合能力强。利用ORTEP 1.076理论计算模拟主客体络合行为,结果表明非共价键相互作用在主客体形成夹心络合物的过程中起着重要作用。  相似文献   

8.
一种新的气相色谱固定液——α,β和γ-环糊精及其衍生物   总被引:14,自引:4,他引:10  
傅若农 《色谱》1992,10(1):14-18
环糊精由六、七或八个吡喃葡萄糖单元组成的环状寡糖化合物,分别为α-环糊精(α-CD),β-环糊精(β-CD)和γ-环糊精(γ-CD)。  相似文献   

9.
以紫外可见分光光度法和荧光光谱法研究了非水溶性meso-四-(2-噻吩基)铜卟啉(简称Cu—TTP)与四种环糊精α—CD、β—CD、γ—CD、TM—β—CD相互作用形成的超分子体系,结果表明Cu-TTP与TM-β-CD形成了1:2的包结物,而与其它三种环糊精主要形成1:1的包结物。在α—CD、β—CD、γ-CD三种母体环糊精中,α—CD与Cu—TTP的包结常数最大;β-CD与其衍生物TM-β-CD相比,TM-β-CD与Cu—TTP的包结常数较大。本文对四种环糊精和Cu-TTP的包结机理作了初步探讨。为铜卟啉和环糊精的相互作用及其超分子体系的研究提供了基础。  相似文献   

10.
设计合成了5-(4-苯甲酰亚胺基苯基)-10,15,20-三苯基卟啉(BATPPH2)及其锌配合物(BATPPZn),并通过1HNMR、IR、UV-Vis、元素分析等方法对化合物的结构加以确认。在中性磷酸盐缓冲溶液中,以荧光光谱法、紫外可见分光光度法和1HNMR法分别研究了BATPPH2和BATPPZn与α,β,γ-环糊精相互作用形成的超分子体系。利用双倒数曲线法计算了BATPPH2-CD和BATPPZn-CD超分子体系的包结常数,结果表明BATPPH2和BATPPZn与γ-CD的包结常数(K1γ-CD,K2γ-CD)最大,γ-CD表现出最强的包结能力,Zn2+的配位作用使包结物的稳定性降低。  相似文献   

11.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

12.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

13.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

14.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

15.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

16.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

17.
18.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

19.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

20.
Quercetin, the polyphenolic compound, which has the highest daily intake, is well known for its protective effects against aging diseases and has received a lot of attention for this reason. Both quercetin 3-O-β-d-glucuronide and quercetin 3′-O-β-d-glucuronide are human metabolites, which, together with their regioisomers, are required for biological as well as physical chemistry studies. We present here a novel synthetic route based on the sequential and selective protections of the hydroxyl functions of quercetin allowing selective glycosylation, followed by TEMPO-mediated oxidation to the glucuronide. This methodology enabled us to synthesize the five O-β-d-glucosides and four O-β-d-glucuronides of quercetin, including the major human metabolite, quercetin 3-O-β-d-glucuronide.  相似文献   

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