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1.
Shibuya H Kitamura C Maehara S Nagahata M Winarno H Simanjuntak P Kim HS Wataya Y Ohashi K 《Chemical & pharmaceutical bulletin》2003,51(1):71-74
The microbial transformation of four Cinchona alkaloids (quinine, quinidine, cinchonidine, and cinchonine) by endophytic fungi isolated from Cinchona pubescens was investigated. The endophytic filamentous fungus Xylaria sp. was found to transform the Cinchona alkaloids into their 1-N-oxide derivatives. 相似文献
2.
Maehara S Simanjuntak P Kitamura C Ohashi K Shibuya H 《Chemical & pharmaceutical bulletin》2011,59(8):1073-1074
We report that the endophytic filamentous fungus Diaporthe sp., isolated from Cinchona ledgeriana and cultivated in a synthetic liquid medium, produces Cinchona alkaloids (quinine, quinidine, cinchonidine, and cinchonine). This shows that Cinchona alkaloids are produced not only in Cinchona plant cells, but also in endophytic microbe cells. 相似文献
3.
Functional group interactions within biologically relevant molecules are among the most influential yet least understood factors in determining their reactive behaviors. Reactions of dimethyl ether ions, which have previously been shown to be site-selective, with four cinchona alkaloids, cinchonine, cinchonidine, quinine and quinidine, have been examined. These reactions are each shown to produce qualitatively similar spectra for the stereoisomeric pairs cinchonidine–cinchonine and quinidine–quinine, but small variations in the relative abundances of the products indicate that some stereoselectivity can be observed. The site selectivity of each of the reagents was investigated by observing the reactions occurring with model subunits of the alkaloids. 相似文献
4.
The room-temperature adsorption of four closely related cinchona alkaloids and three reference quinoline-based compounds from CCl4 solutions onto a polycrystalline platinum surface was characterized by in situ reflection-absorption infrared spectroscopy (RAIRS). The adsorption equilibrium constants (Kads) were found to follow the sequence cinchonine > quinidine > cinchonidine > quinine > 6-methoxyquinoline > lepidine > quinoline. Some of this ordering can be explained by differences in solubility, but quinidine displays a much larger Kads than expected on the basis of its large relative solubility; bonding to the surface must also play a role in determining its behavior. It was determined that each alkaloid binds differently on Pt at saturation coverages. While the quinoline ring of cinchonidine tilts along its long axis to optimize pi-pi intermolecular interactions, in cinchonine it tilts along the short axis and bonds through the lone electron pair of the nitrogen atom instead, and both quinine and quinidine exhibit additional bonding via the methoxy oxygen atom at intermediate concentrations. Perhaps a more surprising result from this work is the fact that cinchonine displays a higher Kads than cinchonidine, quinine, or quinidine even though, according to previous work, it can be easily displaced from the surface by any of those other cinchona alkaloids. A full explanation of these observations requires consideration of the solvent above the adsorbed species. 相似文献
5.
Mariusz Kluska Magdalena Komasińska Joanna Jabłońska Wiesław Prukała 《液相色谱法及相关技术杂志》2018,41(8):451-457
Fully effective antimalarial drugs are yet to be isolated or synthesized, hence the search them continues. The study was aimed at establishing the most suitable conditions for the separation and determination of six biologically active alkaloids, quinoline derivatives, using high performance liquid chromatography with UV/Vis detection. The experiments involved the following derivatives: quinine, quinidine, cinchonine, cinchonidine, acetylcinchonine and acetylquinidine. Of the six stationary phases used, only the naphthylpropyl column enabled the separation of all alkaloids. The octadecyl column, considered by many analysts as a reference, did not provide successful separation. The naphthylpropyl column had also very good validation parameters, including a wide range of linearity, high values of correlation coefficients (0.9990?0.9998) and low standard measurement uncertainty (1.8?2.3?µg?L?1). The newly developed method was employed to evaluate the content of quinine in tonic-like beverages. The naphthylpropyl stationary phase provided ≤5% repeatability of quinine determination. 相似文献
6.
Tsimachidis D Cesla P Hájek T Theodoridis G Jandera P 《Journal of separation science》2008,31(6-7):1130-1136
A new capillary electrophoretic method for the chiral separation of four major Cinchona alkaloids (quinine/quinidine and cinchonine/cinchonidine) was developed using heptakis-(2,6-di-O-methyl)-beta-cyclodextrin as the chiral selector. The inner walls of the separation capillary were modified with a thin polyacrylamide layer, which substantially reduced the electroosmotic flow and improved the chiral resolution and the reproducibility of the migration time of the analytes. Various operation parameters were optimised, including the pH, the capillary temperature, the concentration of the background electrolyte, and the concentration of the chiral selector. Baseline separation of the two diastereomer pairs was achieved in 12 minutes in ammonium acetate background electrolyte pH 5.0 with addition of cyclodextrin in a concentration of 3 mM or higher. 相似文献
7.
Dr. Ichiro Hisaki Eri Hiraishi Toshiyuki Sasaki Dr. Hideo Orita Dr. Seiji Tsuzuki Dr. Norimitsu Tohnai Prof. Dr. Mikiji Miyata 《化学:亚洲杂志》2012,7(11):2607-2614
Quinine, one of Cinchona alkaloids, has been of great interest from medical, synthetic, and supramolecular viewpoints. However, unaccountably, the guest‐free (GF) crystal of quinine containing no solvent or other molecules has not been reported for nearly three decades, although GF crystals of other Cinchona alkaloids, such as quinidine, cinchonidine, and cinchonine, are already known. In this study, we successfully revealed the crystal structure of quinine, which belongs to the P21 space group with the cell parameters of a=6.0587(1), b=19.2492(5), c=22.2824(7) Å, β=92.1646(11)°, and V=2596.83(12) Å3. Interestingly, the crystal has three crystallographically independent molecules in the cell (Z′=3) that are connected through a N(quinoline)???H? O hydrogen bond to form a pseudo three‐two‐fold (32) double‐helical motif. The helical motif is completely different from those observed in GF crystals of other Cinchona alkaloids. Hierarchical comparison on the crystal structures of a series of Cinchona alkaloids including quinine clearly demonstrated that only small structural differences of a molecule, particularly the position of the vinyl group, cause a significant variety of assembly manner in the crystalline state. There have been no reports systematically demonstrating such steric effect in crystals of Cinchona alkaloids, and, therefore, the present system contributes to the design of desired functional crystal structures. 相似文献
8.
Norio Kobayashi Kiyoko Iwai 《Journal of polymer science. Part A, Polymer chemistry》1980,18(1):223-233
New polymeric cinchona alkaloids having favorable structures and properties for asymmetric catalysts have been prepared by radical copolymerization of the alkaloids with acrylonitrile using azobisisobutyronitrile (AIBN) as an initiator. Of the many reaction solvents tried, dimethylformamide (DMF) was found to be the solvent of choice especially for a large-scale synthesis. Alkaloid monomers employed were free dalkaloids, such as quinine, quinidine, cinchonidine, and cinchonine, and modified ones including 9-O-ethoxycarbonylquinine and quinine salts. The copolymers were thermally stable powders, soluble in DMF and DMSO, and insoluble in common organic solvents. They were found to be converted into water-soluble polymeric alkaloids by hydrolysis with alkaline hydrogen peroxide. 相似文献
9.
Magda M. Ayad S.E. Khayyal N.M. Farrag 《Spectrochimica Acta Part B: Atomic Spectroscopy》1985,40(9):1205-1209
A sensitive and rapid microdetermination method has been developed for the determination of cinchona alkaloids via their mercury complex. Different parameters of the procedure have been thoroughly studied. The percentage recoveries for quinine, quinidine, cinchonine and cinchonidine were found to be 98.97 ±0.62, 99.06 ± 0.62, 98.90 ± 0.74, respectively. The results obtained are favourably compared to the official ones. The method is characterised by its specificity, accuracy and good precision. 相似文献
10.
A non-aqueous capillary electrophoretic method developed with quinine and tert.-butyl carbamoylated quinine as chiral selectors for the enantioseparation of N-protected amino acids was applied to the investigation of other quinine derivatives as chiral additives. The optimum composition of the background electrolyte was found to be 12.5 mM ammonia, 100 mM octanoic acid and 10 mM chiral selector in an ethanol-methanol (60:40, v/v) mixture. Under these conditions, a series of chiral acids, as various benzoyl, 3,5-dinitrobenzoyl and 3,5-dinitrobenzyloxycarbonyl amino acid derivatives were investigated with regards to selectand-selector relationships and enantioselectivity employing quinine, quinidine, cinchonine, cinchonidine, tert.-butyl carbamoylated quinine, tert.-butyl carbamoylated quinidine, dinitrophenyl carbamoylated quinine and cyclohexyl carbamoylated quinine as chiral selector. 相似文献
11.
Tertykh V. A. Yanishpolskii V. V. Bereza L. V. Pesek J. J. Matyska M. 《Journal of Thermal Analysis and Calorimetry》2000,62(2):539-544
By means of hydrosilylation reactions between functional olefins and triethoxysilane in the presence of Speier's catalyst
and sol-gel transformations of the reaction products, a number of optically active and complexing alkenes (quinine, quinidine,
cinchonine, cinchonidine, alprenolol, N-allylrhodanine and hemin) were immobilized on the surface of silica. The structures
of the compounds formed and the nature of their bonding with the surface were studied by DRIFT and NMR spectroscopies. The
concentrations of olefins anchored to the surface layer of the silica matrix were estimated by UV spectroscopy.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
Liying Xu Wenyan Zhao Ruimiao Chang Guangbin Zhang Hongfen Zhang Anjia Chen 《Journal of the Iranian Chemical Society》2018,15(7):1477-1483
The purpose of this study was to develop a novel, simple and precise ligand-exchange capillary electrophoresis method to separate the diastereomer pairs of four major cinchona alkaloids (quinine/quinidine and cinchonine/cinchonidine). The l-lysine and copper(II) were chosen as the ligand and the central ion, respectively. Optimal separation conditions of four alkaloids were 4.0 mM l-lys, 2.0 mM copper(II) and 30 mM NH4Ac at pH 8.9 and a applied voltage of 15 kV . Meanwhile, the first-order derivative electropherogram was used for resolving the overlapping peaks of cinchonidine and quinidine. Under the optimum condition, good linearities were obtained with correlation coefficients from 0.9908 to 0.9935. The limits of detection (LOD, S/N?=?3) and the limits of quantitation (LOQ, S/N?=?10) ranged from 0.24 to 0.41 μg/mL and from 0.73 to 1.35 μg/mL, respectively. The recoveries ranged between 95.38 and 106.03%. The proposed ligand-exchange capillary electrophoresis method was suitable for the quantitative determination of four cinchona alkaloids in some preparations such as Compound Quinine Injection, Tonic Water and Klorane quinine and Vitamin B complex Shampoo. 相似文献
13.
Cinchona alkaloids catalyze the enantioselective Mannich reaction of beta-keto esters with acyl aryl imines. The reaction requires 10 mol % of cinchonine or cinchonidine. The reaction products are obtained in good yields (81-99%), high enantioselectivities (80-96% ee), and in diastereoselectivities that range from 1:1 to >95:5. The cinchonine-catalyzed reaction provides access to highly functionalized building blocks used in the asymmetric synthesis of a dihydropyrimidone and beta-amino alcohol. 相似文献
14.
Quinoline-derived compounds exhibit the following relative chemisorption strengths from CCl4 solutions onto platinum surfaces, as determined by in-situ infrared spectroscopy: quinine, quinidine > cinchonidine > cinchonine > 6-methoxyquinoline > lepidine > quinoline. This sequence explains nonlinear enantioselectivity effects with cinchona chiral modifiers in hydrogenation catalysis. 相似文献
15.
Some cinchona alkaloids, the quinine/quinidine and cinchonine/cinchonidine pairs, are extracted by ion-pair formation with some chiral amino acids and d-camphorsulfonic acid. Their extraction behaviors are examined and the differences between the two isomers are compared. These alkaloids are extracted into chloroform in the pH range 4–7 as the 1:1 ion-pair with the organic acid. The relationship between the distribution ratio of the ion-pair and pH is discussed. In the pH range between the pKa1 and pKa2 values of these alkaloids, logarithmic plots of the distribution ratio are independent of pH. In this pH region, the extraction constants are determined and the differences caused by the ion-pair formation are discussed. 相似文献
16.
Highly stereoselective, uniformly sized molecularly imprinted polymers (MIPs) for cinchona alkaloids, cinchonine (CN) and cinchonidine (CD), were prepared using methacrylic acid (MAA) as a functional monomer and ethylene glycol dimethacrylate (EDMA) as a cross-linker. The MIPs were evaluated using a mixture of phosphate buffer and acetonitrile as the mobile phase. The CN- and CD-imprinted MAA-co-EDMA polymers can recognize the respective template molecule more than the other diastereomer, and afford an excellent diastereomer separation of CN and CD. In addition, the MIPs gave diastereomer separations of structurally related compounds, quinidine and quinine. The retentive and stereoselective properties of those compounds on the MIPs suggest that electrostatic and hydrophobic interactions can work to recognize these compounds. Furthermore, thermodynamic studies reveal that the entropy-driven effect is significant at mobile-phase pH 5.4, while the enthalpy-driven interactions seem to be dominant at mobile-phase pH 9.6. 相似文献
17.
Rapid determination of cyclamate in foods by solid-phase extraction and capillary electrophoresis 总被引:1,自引:0,他引:1
Horie M Ishikawa F Oishi M Shindo T Yasui A Ito K 《Journal of chromatography. A》2007,1154(1-2):423-428
A method for the determination of cyclamate in food was developed using solid-phase extraction (SPE) and capillary electrophoresis (CE) with indirect ultraviolet (UV) detection. A 5-10 g sample in 0.1 mol/L hydrochloric acid was homogenized and made up to a volume of 50 mL with 0.1 mol/L hydrochloric acid. After the sample was centrifuged, 25 mL of supernatant was loaded into an Oasis HLB SPE cartridge. The cartridge was washed with 2 mL of demineralized water followed by 2 mL of 50% aqueous methanol, and cyclamate was eluted with 4.5 mL of 50% aqueous methanol. The eluate was added to a solution of sodium propionate (internal standard) for CE analysis. The cyclamate in the eluate was electrophoresed on a fused-silica capillary using 1 mmol/L hexadecyltrimethylammonium bromide and 10 mmol/L potassium sorbate as a running buffer. Detection and reference wavelengths of cyclamate determined with a UV detector were 300 and 254 nm, respectively. The calibration curves for cyclamate showed good linearity in the range of 2-1000 microg/mL and the limits of detection in beverage, fruit in syrup, jam, pickles and confectionary are sample dependent and ranged from 5-10 microg/g. The recovery of cyclamate added at a level of 200 microg/g to various kinds of foods was 93.3-108.3% and the relative standard deviation was less than 4.9% (n=3). A number of commercial samples were analyzed using the proposed method. Cyclamate was detected in one waume, two pickles, and two sunflower seeds. The quantitative values determined with CE correlated to those from high-performance liquid chromatography (HPLC) (the detected values of cyclamate in a sunflower seed measured by CE and HPLC were 3.40 g/kg and 3.51 g/kg, respectively). This analytical method for cyclamate using CE is especially suitable for use in the field. 相似文献
18.
Garret M. Miyake Hiroki Iida Hai‐Yu Hu Zhenglin Tang Eugene Y.‐X. Chen Eiji Yashima 《Journal of polymer science. Part A, Polymer chemistry》2011,49(24):5192-5198
Four novel dynamic helical poly(phenylacetylene)s bearing cinchona alkaloids as pendant groups were synthesized starting from the commercially available cinchona alkaloids, cinchonidine, cinchonine, quinine, and quinidine, by the polymerization of the corresponding phenylacetylene monomers with a rhodium catalyst. These polymers exhibited an induced circular dichroism (ICD) in the UV–visible region of the polymer backbones in solution, resulting from the preferred‐handed helical conformation induced by the optically active cinchona alkaloid pendants. In response to the solvent used, their Cotton effect patterns and intensities were significantly changed accompanied by the changes in their absorption spectra probably due to the changes in their helical conformations, such as the inversion of the helical sense or helical pitch of the polymers. When these helical polymers were used as polymeric organocatalysts for the asymmetric conjugated addition and Henry reactions, the optically active products with a modest enantiomeric excess were obtained whose enantioselectivities were comparable to those obtained with the corresponding cinchona alkaloid‐bound monomers as the catalysts. However, we observed a unique enhancement of the enantioselectivity and a reversal of the stereoselectivity for some helical polymers, suggesting the important role of the helical chirality during the asymmetric organocatalysis. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
19.
Lambers M Beijer FH Padron JM Toth I de Vries JG 《The Journal of organic chemistry》2002,67(14):5022-5024
The four naturally occurring cinchona alkaloids were subjected to hydroformylation to create an extra functional group that allows immobilization. Cinchonidine, quinine, and quinidine, could be hydroformylated with virtually complete terminal selectivity, using a rhodium/tetraphosphite catalyst. The cinchonidine aldehyde was reduced to the alcohol and subjected to reductive amination with benzylamine. 相似文献
20.
Optically active syn- or anti-beta-substituted-alpha-amino acid derivatives are prepared in 94 to >/=99% ee and 66-98% ds by reaction of the Schiff base acetate of glycine tert-butyl ester with chiral, nonracemic B-alkyl-9-BBN derivatives in the presence of the Cinchona alkaloid, cinchonidine (CdOH) or cinchonine (CnOH), base, and lithium chloride. 相似文献