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Ionic liquids(ILs) are salts composed entirely of anions and cations in a liquid state at or near room temperature, which have a variety of good physicochemical properties such as low volatility and high stability. This paper mainly reviewed the research overview of ILs in the application of traditional Chinese medicine(TCM) volatile oil preparation technology. Firstly, it briefly introduced the application of TCM volatile oil preparation technology and composition classification and physicochemical properties of ILs, and then summarized the application of ILs in the extraction, separation, analysis, and preparation of TCM volatile oil. Finally, the problems and challenges of ILs in the application of TCM volatile oil were explained, and the application of ILs in TCM volatile oil in the future was prospected.
Subject(s)
Ionic Liquids/chemistry , Oils, Volatile/analysis , Medicine, Chinese Traditional , Cations , Biological Products , TechnologyABSTRACT
Objective:To explore the effect of large-volume versus restrictive fluid resuscitation on hemodynamics and prognosis in patients with severe acute pancreatitis (SAP). Methods:A total of 102 patients with severe acute pancreatitis who received treatment in The Second People's Hospital of Hefei, China between March 2018 and December 2020 were included in this study. They were randomly assigned to undergo large-volume fluid resuscitation (control group, n = 51) or restrictive-volume fluid resuscitation (study group, n = 51). Hemodynamic indexes, intra-abdominal pressure and pulmonary function were compared between the two groups before and after resuscitation. All patients were followed up for 28 days after admission and their prognosis was recorded. Results:At 12 and 24 hours of resuscitation, intrathoracic blood volume index, global end-diastolic volume index, cardiac index, and central venous pressure in the study group were significantly higher than those in the control group (all P < 0.05). At 6 hours of resuscitation, cardiac index and central venous pressure in the study group were (4.87 ± 0.48) and (11.04 ± 2.08), respectively, which were significantly higher than those in the control group [(4.53 ± 0.57), (9.48 ± 1.67), t = 3.25, 4.17, both P < 0.05). Before resuscitation, there was no significant difference in intra-abdominal pressure between the two groups ( P > 0.05). After resuscitation, intra-abdominal pressure in each group was significantly lower compared with that before resuscitation (both P < 0.05). After resuscitation, intra-abdominal pressure in the study group was significantly lower than that in the control group [(12.78 ± 2.35) cmH 2O vs. (15.01 ± 2.42) cmH 2O, t = 4.72, P < 0.05). Before resuscitation, there were no significant differences in PaO 2 and oxygenation index between two groups (both P < 0.05). After resuscitation, PaO 2 and oxygenation index in each group were significantly higher compared with those before resuscitation (both P < 0.05). After resuscitation, PaO 2 and oxygenation index in the study group were significantly higher than those in the control group ( t = 3.02, 5.55, both P < 0.05). The incidence of abdominal compartment syndrome and the incidence of invasive mechanical ventilation in the study group were 27.45% (14/51) and 35.29% (18/51), respectively, which were significantly lower than those in the control group [47.06% (24/51), 56.86% (29/51), χ 2 = 4.19, 4.77, both P < 0.05). There were no significant differences in the incidence of multiple organ dysfunction syndrome, acute renal injury, abdominal drainage rate, mortality between the two groups (all P > 0.05). Conclusion:Compared with large-volume fluid resuscitation, restrictive-volume fluid resuscitation can better improve hemodynamic indexes and pulmonary function, greatly decrease intra-abdominal pressure, and improve prognosis in patients with severe acute pancreatitis.
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Objetivo: O objetivo deste estudo foi avaliar o potencial antifúngico de um conjunto de sais imidazólicos (SI) frente a Candida albicans. Materiais e métodos: A avaliação an-tifúngica dos SI foi realizada por meio do teste de difusão em ágar, utilizando uma cepa de Candida albicans (ATCC 90028). Cinco diferentes SI foram sintetizados e testados no presente estudo: brometo de 1,8-bis(metilimidazólio-1-il) octano (MImC8MImBr2), metanossulfonato de 1,12-bis(-metilimidazólio-1-il) dodecano (MImC12MIm(MeS)2), clo-reto de 1-n-hexadecil-2,3-dimetilimidazólio (C16DMImCl), metanossulfonato de 1,10-bis(metilimidazólio-1-il) decano (MImC10MIm(MeS)2) e brometo de 1,10-bis(metilimidazólio--1-il) decano (MImC10MImBr2). O cloreto de cetilpiridíneo (C16PyrCl) foi utilizado como composto de referência e as soluções de digluconato de clorexidina (C34H54Cl2N10O14) e salina (NaCl 0,9%) foram utilizadas como controles po-sitivo e negativo, respectivamente. Resultados: Dentre os SI testados, MImC12MIm(MeS)2, MImC10MIm(MeS)2 e MImC10MImBr2 apresentaram os seguintes valores para os halos de inibição formados: 28,00 mm, 20,50 mm e 18,75 mm, respectivamente. Esses valores foram similares ou superiores inclusive aos encontrados para o controle positivo (14,87 mm) e o composto de referência (0 mm). Discussão: Os SI podem apresentar uma alternativa promissora às terapias com antifúngicos convencionais, concordando com estudos prévios. Entretanto, mais estudos in vitro e in vivosão necessários para avaliar o potencial antifúngico destes compostos frente a biofilmes multiespécies de C. albicans. Conclusão: Baseado nestes resultados, três dos SI testados apresentam atividade antifúngica in vitro promissora frente à Candida albicans.
Aim: This study aims to evaluate the antifungal potential of imidazolium salts (IS) against Candida albicans. Material and methods: Antifungal evaluation of the IS was perfor-med using the disk diffusion test, using a strain of Candida albicans (ATCC 90028). Five different IS were synthesized and tested in the present study: 1,8-bis(methylimidazolium-1-yl) octane bromide (MImC8MImBr2), 1,12-bis(methylimida-zolium-1-yl) dodecane methanesulfonate (MImC12MIm(-MeS)2), 1-n-hexadecyl-2,3-dimethylimidazolium chloride (C16DMImCl), 1,10-bis(methylimidazolium-1-yl) decane methanesulfonate (MImC10MIm(MeS)2) e 1,10-bis(me-thylimidazolium-1-yl) decane bromide (MImC10MImBr2). Cetylpyridinium chloride (C16PyrCl) was used as a reference substance. Chlorhexidine (C34H54Cl2N10O14) and saline (NaCl 0,9%) solutions were positive and negative controls, respectively. Results: Among the tested IS, MImC12MIm(-MeS)2, MImC10MIm(MeS)2 and MImC10MImBr2 showed the following values for inhibition halos: 28,00 mm, 20,50 mm and 18,75 mm, respectively. These values were similar or superior than those found for the positive control (14.87 mm) and reference (0 mm) substances. Discussion: IS can be a promising alternative to antifungal conventional therapies, as exemplified in previous studies. However, further in vitro and in vivo studies are needed to assess the antifungal potential of these compounds against Candida--mixed biofilms.Conclusion: Based on these results, three IS, tested in this study, have in vitro promissing antifungal potential against Candida albicans.
Subject(s)
Salts , Candida albicans , Antifungal AgentsABSTRACT
A enzima L-asparaginase de Escherichia coli (ASNase) é um biofármaco indicado para o tratamento de leucemia linfoblástica aguda, mas que pode causar reações de hipersensibilidade nos pacientes tratados. Na tentativa de amenizar esse efeito, foi desenvolvida a PEG-ASNase (enzima conjugada com polietilenoglicol) que apresenta a vantagem de ser menos imunogênica e ter maior meia-vida biológica. Mais recentemente, novas abordagens têm sido desenvolvidas visando aprimorar os processos de PEGuilação por meio de reações sítio dirigidas, por exemplo N-terminal, a fim de promover maior similaridade lote a lote e controle das características farmacocinéticas e farmacodinâmicas do biofármaco. Porém, existe ainda uma limitação associada à hidrólise do PEG reativo, desta forma surge a necessidade de procurar solventes alternativos para a PEGuilação que permitam manter a estabilidade das proteínas, aumentar o rendimento de PEGuilação e a estabilidade do PEG reativo. Nesse trabalho, líquidos iônicos foram investigados como solventes alternativos para a peguilação N-terminal de PEG-ASNase. Para tal, a estabilidade de ASNase em Lis foi investigada em LIs da família metil-imidazol, analisando a influência do aumento da cadeia alquílica e de diferentes ânions. A estabilidade da ASNase é favorecida quando em contato com Lis relativamente hidrofóbicos ([C2mim]Cl, [C4mim]Cl e [C6mim]Cl), mas sua a atividade é prejudicada quando o LI é muito polar, como o [C4mim][(CH3)2PO4] ou anfifílico como o [C12mim]Cl. Apesar de seu efeito desnaturante, o [C4mim][(CH3)2PO4] resultou no maior rendimento da reação de PEGuilação da ASNase (56%) quando empregado a 75% e a reação realizada em 10 min. O [C4mim]Cl resultou em rendimento semelhante ao tampão fosfato (~ 49%), mas ambos os LIs reduziram a poliPEGuilação. Portanto, os Lis [C4mim]Cl e [C4mim][(CH3)2PO4] fornecem uma alternativa viável à reação de PEGuilação pela redução na formação de espécies poliPEGuiladas, o que facilitaria os processos de purificação e permitiria maior controle lote a lote da reação, bem como pelo aumento do rendimento da reação no caso do [C4mim][(CH3)2PO4]
Escherichia coli L-asparaginase enzyme (ASNase) is a biopharmaceutical indicated for the treatment of acute lymphoblastic leukemia, but may cause hypersensitivity in the patients used. In an attempt to alleviate this effect, PEG-ASNase (polyethylene glycol conjugated enzyme) was developed, which has the advantage of being less immunogenic and having a longer biological half-life. More recently, new approaches have been applied to improve PEGylation processes through targeted sites, for example N-terminal, in order to promote greater similarity to the batch and control of the pharmacokinetic and pharmacodynamic characteristics of the biopharmaceutical. However, there is still a limitation associated with reactive PEG hydrolysis, thus increasing the need to look for alternative PEGylation solvents to maintain protein stability, increase PEGylation yield and use reactive PEG. In this work, ions were investigated as alternative solvents for the N-terminal PEG-ASNase. For example, a stability of ASNase in ILs was investigated in imidazole ILs by analyzing the influence of increased alkyl chain and different anions. ASNase stability is enhanced when in contact with relatively hydrophobic ILs ([C2min]Cl, [C4min]Cl and [C6min]Cl), but its activity is impaired when very polar ILs such as [C4min][(CH3)2PO4] or amphiphilic as [C12mim]Cl. Despite its denaturing effect, [C4min][(CH3)2PO4] resulted in higher yield of ASNase PEGylation reaction (56%) when employed at 75% and reaction performed in 10 min. [C4min]Cl yielded similar phosphate buffer yield (~ 49%), but both ILs reduced polyPEGylation. Therefore, [C4min]Cl and [C4min][(CH3)2PO4] Ils may use a viable alternative to the PEGylation reaction and reduce the formation of polyPEGylated species, or that facilitate purification processes and allow for greater batch use of the solution, as well as increased reaction yield in the case of [C4min][(CH3)2PO4]
Subject(s)
Ionic Liquids , Asparaginase/analysis , Escherichia coli/classification , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Protein StabilityABSTRACT
Flavonoids have many physiological and pharmacological activities. Ionic liquids are increasingly used in the extraction of flavonoids from natural products due to their unique properties. In this paper, various extraction methods of natural flavonoids were reviewed and summarized. The effects of anion and cation type, length of carbon chain, and bond cooperation on the extraction of natural flavonoids in ionic liquids, especially imidazole type ionic liquids, were also reviewed. Suggestions on selection of extractant for ionic liquid extraction of flavonoids were given. The advice of the green recovery of ionic liquids and the development of edible ionic liquids for the future direction of development were suggested. This study will lay the foundation for the basic research and industrial application of ionic liquids in the extraction of natural flavonoids.
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Panax ginseng is a traditional Chinese medicine with significant pharmaceutical effects and wide application. Through orientational modification and transformation of ginsenoside glycosyl, rare ginsenosides with high antitumor activities can be generated. Traditional chemical methods cannot be applied in clinic. because of extremely complex preparation technologies and very high cost Transformations using microorganisms and their enzymatic systems provide the most feasible methods for solving the main problems. At present, the key problems in enzymatic synthesis of ginsenosides include low specific enzyme activities, identity of enzymes involved in the enzymatic synthesis, and their catalytic mechanisms, as well as nonsystematic studies on structural bioinformatics; specificity of enzymatic hydrolysis for saponin glycosyl has been rarely studied. Many reviews have been reported on glycosidase molecular recognition, immobilization, and biotransformation in ionic liquids (ILs), whereas ginsenoside transformation and application have not been systematically studied. To evaluate theoretical and applied studies on ginsenoside-oriented biotransformation, by reviewing the latest developments in related fields and evaluating the widely applied biocatalytic strategy, this review aims to evaluate the ginsenoside-oriented transformation method with improved product specificity, increased biocatalytic efficiency, and industrial application prospect based on the designed transformations of enzyme and solvent engineering of ILs. Therefore, useful theoretical and experimental evidence can be obtained for the development of ginsenoside anticancer drugs, large-scale preparation, and clinical applications in cancer therapy.
Subject(s)
Biocatalysis , Ginsenosides , Glycoside Hydrolases , Panax , SaponinsABSTRACT
A method based on in situ formed ionic liquids microextraction-ultra performance liquid chromatography(ISFILM-UPLC) was established for the determination of vancomycin in human serum.The samples were pretreated by vortex and centrifugation.[C6MIM] [Br] and NaPF6 were applied as the extracting agent,and Metronidazole as the internal standard.Methanol was applied to redissolve the precipitate.The separation was carried out on a BEH C18 column,and the mobile phase consisted of methanol and 0.05 mol/L monopotassium phosphate solution.The flow rate was 0.2 mL/min,the injection volume was 5 μL,and the column temperature was 18 ℃.The key parameters of this method such as the specificity,accuracy and precision were validated.This method showed good correlation with the immunoassay.It shows great potential for the application in clinical practice.
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To establish a method for the simultaneous determination of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of Malus halliana by ultrasonic-assisted ionic liquid coupled with RP-HPLC. An Agilent TC-C₁₈ (4.6 mm×250 mm, 5 μm) column was used, with the mobile phase of acetonitrile and 1% phosphoric acid-water (20∶80) by gradient elution at the detection wavelength of 270 nm. The flow rate was 0.8 mL•min⁻¹, and chromatographic column temperature was controlled at the room temperature. Under the optimized conditions, the linear ranges for phloridzin, 3-hydroxy phloridzin and quercitrin were 0.9-112.5 μg (r = 0.999 6), 0.093 2-11.65 μg (r = 0.999 1) and 0.097 2-12.15 μg (r = 0.999 8), respectively. The average recoveries of the three constituents were 99.35%, 98.80% and 98.19%, respectively. The method was environmental friendly, rapid, accurate and highly reproducible, and so suitable for the quantitative analysis of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of M. halliana.
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Using six kinds of ionic liquids as extractants, ultrasonic-assisted extraction coupled with HPLC method was developed for the simultaneous determination of wilforgine, wiforizine, triptophenolide, wilforine and triptoquinone A in Tripterygium hypoglaucum. The separation was performed on an Inertsil ODS-4 column with the mobile phase of acetonitrile-0.1% phosphoric acid in gradient elution at a flow rate of 0.75 mL•min⁻¹. Detection wavelength was 220 nm and the column temperature was 30℃. Under the optimal extractions, the results showed that triptophenolide and triptoquinone A had the highest extraction yield by using 0.6 mol•L⁻¹ [BMIm]PF6 methanol solution as extraction solvent with the solid-liquid ratio of 1∶10. The calibration curves of triptophenolide and triptoquinone A showed a good linearity in the range of 0.000 65-0.026, 0.066 55-2.662 μg (r=0.999 9)respectively. The average recovery was 102.4% and 97.90% with RSD of 2.5% and 1.5%, respectively. Wilforgine, wiforizine and wilforine had the highest extraction yield when using 0.6 mol• L⁻¹ [BMIm]PF6absolute ethanol solution as extraction solvent with the solid-liquid ratio of 1∶10. The content of wilforgine, wiforizine and wilforine from 0.023 9-0.956, 0.002 7-0.108, 0.006 4-0.256 μg showed a good linearity (r=0.999 9), and the average recovery was 100.6%,99.50% and 98.70% with RSD of 2.1%,1.9% and 2.7%, respectively. The results indicated that this method is convenient, reliable and green, and can be used as a reliableanalytical method for the quality control of T.hypoglaucum.
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ZnO nanoparticles ( ZnO NPs ) were obtained by a direct precipitation method. With the as-prepared ZnO NPs as seeds, Au/ZnO heterostructure was synthesized by seed-mediated growth method without any surfactant, and the diameters of ZnO NPs and Au NPs were about 50 nm and 10 nm, respectively. Then ionic liquids (ILs), trihexyltetradecylphosphonium bis (trifluoromethylsulfonyl) imide ([P(C6)3C14] [ Tf2 N] ) , and functionalized graphene ( GN ) were prepared under room temperature. The ILs as bridges could connect Au/ZnO heterostructure to form a new kind of graphene nanocomposite, Au/ZnO/GN. Then the penicillinase and hematein were immobilized on Au/ZnO/GN. And the biosensors based on penicillinase-hematein-Au/ZnO/GN (PH-AZG) were used for detecting penicillin G. In PBS buffer solution (pH 7. 0), PH-AZG exhibited a detection range from 2 . 5 × 10-14 to 3 . 3 × 10-6 mol/L with a detection limit of 1 . 5 × 10-14 mol/L (S/N≥3). Five PH-AZG electrodes were prepared with the same conditions, and the RSDs for their current response were less than 3. 2%. Furthermore, the standard curves were linear in the range of 5× 10-14-5×10-7 mol/L for milk. The average recoveries were 99. 7%-101. 4% with RSDs of 2. 3%-3. 5%(n=5). The method is sensitive and repeatable, and can be applied to the field of residue analysis about penicillins G with low concentration levels.
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El comportamiento y el desempeño electroquímico del electrodo de pasta de carbono químicamente modificado por un líquido iónico (EPCQM), en la detección del galato de propilo, se investigaron matemáticamente desde el punto de vista de la estabilidad del estado estacionario. El modelo matemático correspondiente se analizó por medio de la teoría de estabilidad lineal y análisis de bifurcaciones. Los resultados de modelaje son comparados con los experimentales (para este sistema y semejantes), bien como con los teóricos para otros casos.
The behavior and the electrochemical function of the carbon paste electrode, chemically modified by ionic liquid, have been investigated mathematically from the point of view of steady-state stability. The corresponding mathematical model is analyzed by linear stability theory and bifurcation analysis. The modeling results are being compared with experimental results (for this system and for the similar ones), and with theoretical results for other cases.
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A simple and green method for the determination of trace bisphenol A( BPA) was established by coupling supported ionic liquid solid phase extraction to β-cyclodextrin modified ionic liquid carbon paste electrode-based electrochemical detection ( SILs-SPE-ED) . The synthesized imidazolium ionic liquid modified styrene type macroporous resin was used as adsorbent for SPE of BPA. The critical parameters that affect the extraction efficiency were optimized, including 0. 4 g of packing material quantity, 200 mL of sample solution at pH 7. 0, 5 mL of methanol as an eluent solvent, and 4. 5 mL/min of the SPE flow rate. Dynamic adsorption test showed that the maximum adsorption capacity of BPA on the SILs-SPE cartridge was 10. 1 mg/g, and the enrichment factor was 40 . The calibration curve showed a good linearity between the anodic current and the BPA concentration in the range of 1. 0×10-8-1. 0×10-6 mol/L (i. e. 2. 3-228μg/L). The detection limit was 4. 16×10-9 mol/L (equal to 0. 95 μg/L). The SILs-SPE-ED method was applied to the analysis of water and plastic samples and the results agreed well with HPLC method.
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Objective: To evaluate the in vitro percutaneous absorption profiles of ginsenoside Rh1 using ionic liquids [BMIM][Cl] as a novel permeation enhancer and to investigate the mechanism. Methods: Mice skin and porcine skin were used as skin model. Oil acid, isopropyl myristate, and menthol were used as comparing skin enhancers. The solubility of Rh1 (with or without enhancer) in water was measured by shake-flask method. Skin permeation experiment was performed using Franz diffusion cells. Skin structure change after treatment of [BMIM][Cl] was measured by FTIR. Results: By comparing with commonly used enhancers, 5% [BMIM][Cl] significantly increased the solubility of Rh1 and gave an excellent improvement on the skin penetrability of Rh1. The FTIR results suggested that [BMIM][Cl] accelerated the drug skin permeation by disrupting the lipid bilayer of skin stratum corneum. Conclusion: [BMIM][Cl] can serve as a novel skin permeation enhancer, and show a broad application prospect in transdermal drug delivery system.
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Graphene/Room temperature ionic liquids ( GN/IL ) nanocomposite was prepared by grinding graphene and ionic liquid 1-butyl-3-methylimidazolium bromide ( BMIMPF6 ) which mixed together in appropriate proportion. Atomic force microscopy ( AFM ) was utilized to characterize the formation of the GN-ILs. Due to the synergistic effect between ionic liquids and graphene, the nanocomposite exhibited excellent performance toward H2 O2 reduction. A novel uric acid ( UA) electrochemical sensor was fabricated based on uricase-GN/IL modified glassy carbon electrode. The experimental results showed that the response displayed a good linear response toward UA in the concentration range from 0. 002-4. 5 mmol/L. The corre1ation coefficient was 0. 995 and the detection limit was 0. 85 μmol/L. The easily prepared electrochemical sensor had favorable stability and selectivity and could be applied to the quick determination of UA in human serum, thus providing a new UA detection method for clinical trial.
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Se midieron densidades e índices de refracción de mezclas binarias de agua, metanol y etanol con 1-Etil-3-metilimidazolio Etilsulfato (EMIM-EtSO4) y de etanol con 1-Metil-3-metilimidazolio Metilsulfato (MMIM-MeSO4) en el rango de temperatura de (298,15, 308,15 y 318,15) K. Se calcularon los volúmenes de exceso molar (V M E) y la desviación del índice de refracción (d n ), que se ajustaron a una ecuación polinomial de Redlich-Kister de orden cuatro.
Densities and refractive indices of binary mixtures of water, methanol and ethanol with 1-Ethyl-3-methylimidazolium Ethylsulfate (EMIM-EtSO4) and ethanol with 1-Methyl-3-methylimidazolium Methylsulfate (MMIM-MeSO4) in the temperature range (298.15, 308.15 and 318.15) K were measured. The excess of molar volumes (V M E) and the deviation of the refractive index (d n ), were fitted to an order fourth polynomial equation of Redlich-Kister.
Determinam-se densidades e índices de refração de misturas binárias de água, metanol e etanol com 1-Etil-3-metilimidazólio Etilsulfato (EMIM-EtSO4) e de etanol com 1-Metil-3-metilimidazólio Metilsulfato (MMIM-MeSO4) no intervalo de temperatura (298,15, 308,15 e 318,15) K. Se calcularam os volumes de excesso molar (V M E) eo desvio do índice de refração (d n ), ajustados áuma equação polinomial de Redlich-Kisterde ordem quatro.
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Objective To explore an easily-controllable, environmentally-friendly method for synthesizing monastrol and its derivatives. Methods Monastrol and its derivatives were synthesized using (substituted) benzaldehyde, ethyl acetoacetate and thiourea (or urea) as the material through a Biginelli reaction catalyzed by green room temperature ionic liquid 1-butyl-3- methylimidazolium-L-camphorsulfonate under microwave irradiation without solvent. Results The green room temperature ionic liquid 1-butyl-3-methylimidazolium-L-camphorsulfonate catalyzed Biginelli reaction in obtaining the title compound under microwave irradiation without solvent. The process was easy to operate, time saving and environmentally-friendly. Conclusion Microwave-accelerated solvent-free Biginelli reaction using green room temperature ionic liquid 1-butyl-3-methylimidazolium-L- camphorsulfonate as catalyst is a convenient and environmentally-friendly method for synthesizing monastrol and its derivatives.
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Objective To explore an easily-controllable, environmentally-friendly method for synthesizing monastrol and its derivatives. Methods Monastrol and its derivatives were synthesized using (substituted) benzaldehyde, ethyl acetoacetate and thiourea (or urea) as the material through a Biginelli reaction catalyzed by green room temperature ionic liquid 1-buty-3- methylimidazolium-L-camphorsulfonate under microwave irradiation without solvent. Results The green room temperature ionic liquid 1-buty-3-methylimidazolium-L-camphorsulfonate catalyzed Biginelli reaction in obtaining the title compound under microwave irradiation without solvent. The process was easy to operate, time saving and environmentally-friendly. Conclusion Microwave-accelerated solvent-free Biginelli reaction using green room temperature ionic liquid 1-buty-3-methylimidazolium-L- camphorsulfonate as catalyst is a convenient and environmentally-friendly method for synthesizing monastrol and its derivatives.
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The effects of adsorption time, solid-liquid ratio, sample concentration, flow rate on the adsorption properties of supported ionic liquids(the N-methylimidazolium functionalized silica, SilprMin) for flavonoids were investigated. The results indicated that the adsorption equilibrium for tested compounds, genistein, luteolin and quercetin, was achieved within 30 min, the adsorption efficiencies of these three compounds were improved with the increase of solid-liquid ratio, and decreased with the increase of their concentrations. Moreover, the adsorption isotherm data of the three tested compounds were in good concordance with the Langmuir model. The saturated adsorption capacity of SilprMim for genistein, luteolin and quercetin was 47.7, 52.5 and 63.2 mg/g, respectively. Adsorption efficiency of SilprMim could reach more than 90% at a sample flow rate of 0.5～1.5 mL/min. Using methanol as eluent, the saturated desorption efficiencies of genistein, luteolin and quercetin were 86.1%, 83.3% and 84.6%, respectively. The elution order of the three tested flavonoids was genistein, luteolin and quercetin. SilprMim had strong adsorption and separation capacity for three tested flavonoids, which was hopeful to be applied in separation and purification of naturally occurring flavonoids.
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Los líquidos iónicos son excelentes medios para reacciones catalíticas, debido a que pueden ser utilizados para optimizar o reciclar los catalizadores homogéneos. En este trabajo se describe el uso de varios líquidos iónicos de bajo punto de fusión (-30 – -34 °C), basados en derivados de la piridina, para utilizarlos en la hidroaminación de olefinas activadas, catalizada por complejos de Ni(II). El catalizador [Ni(Pigiphos)(NCCH3)](ClO4)2 presenta buena actividad cuando el medio de reacción es un líquido iónico (TON hasta 172) y el sistema catalizador/líquido iónico se puede reciclar por lo menos dos veces.
Ionic liquids are excelent solvents for catalytic reactions because they can optimize and/or recycle the homogeneous catalysts. In this work we describe the use of ionic liquids with low melting point (-30 – -34 °C) –based on pyridine derivatives– in the hydroamination reaction of activated olefins catalyzed by Ni(II) complexes. The catalyst [Ni(Pigiphos) (NCCH3)](ClO4)2 allows good activity in ionic liquids (TON up to 172) and the catalyst/ ionic liquid system can be recycled at least 2 times.
Os líquidos iónicos são exelentes meios para reacçãos catalíticas, devido a que podem ser utilizados para otimizar y/ou reciclar os catalisadores homogêneos. Neste trabalho descrive-se a aplicação de varios líquidos iónicos de baixo ponto de fusão (-30 – -34 °C) –baseados em derivados de piridina– para ser utilizados na hidroaminação de olefinas activadas, catalisada por complexos de Ni(II). O catalisador [Ni(Pigiphos)(NCCH3)](ClO4)2 apresenta boa actividade quando em meio de reacção e um lìquido iónico (TON hasta 172) e o sistema catalizador/líquido iónico se pode reciclar pelo menos 2 vezes.