Ionic liquid-assisted catalysis for glycosidation of two triterpenoid sapogenins

2019 ◽  
Vol 43 (43) ◽  
pp. 16881-16888 ◽  
Author(s):  
Tenghe Zhang ◽  
Xinlu Li ◽  
Hang Song ◽  
Shun Yao

In order to study the universality of ionic liquids-assisted glycosidation and explore their catalytic behaviors together with potential, oleanolic acid and ursolic acid were selected to establish catalytic system as typical triterpene sapogenins.

2021 ◽  
Author(s):  
Guiling Shi ◽  
Ran Zhai ◽  
Haoran Li ◽  
Congmin Wang

A dual functionalized ionic liquid catalytic system was developed for the reaction between CO2 and propargylic alcohols, and exhibited excellent performance and good reusability, even under a low concentration of CO2 in a gram-scale reaction.


2019 ◽  
Vol 21 (3) ◽  
pp. 567-577 ◽  
Author(s):  
Wenfeng Zhao ◽  
Xiaoping Chi ◽  
Hu Li ◽  
Jian He ◽  
Jingxuan Long ◽  
...  

A sustainable and recyclable ionic liquid catalytic system is developed to be efficient in N-methylation or N-formylation of amines with CO2 under mild conditions.


Author(s):  
R. V. Aliyeva ◽  
Y. M. Babashova ◽  
M. J. Khamiyev ◽  
Sh. R. Bagirova ◽  
H. R. Azizbeyli

AbstractThe article is dedicated to the development of processes for (oligo)alkylation of petroleum fractions rich in aromatic hydrocarbons, with α-olefins (hexene-1, octene-1, decene-1) in the presence of ionic-liquid catalytic systems and the study of the properties of the products obtained. Alkylation reactions were carried out in the presence of chloroaluminate ionic liquids; for the first time a (nano)metal-polymer composite (NMPC) was used in the catalytic system as a modifier, and zinc chloride (ZnCl2) was used in the catalytic system as a component and the results were compared. It has been shown that these ionic liquid catalytic systems (ILCS) are suitable for (oligo)alkylation reactions and the use of these additives in their composition will lead to efficient alkylation. The products obtained were analyzed by IR-, NMR- spectroscopy, fluorescent indicator adsorption methods, and size exclusion chromatography. It was shown that these petroleum fractions rich in aromatic hydrocarbons can be used as alkylation components, and depending on the composition of the ILCS, it is possible to regulate the molecular, thermophysical and other characteristics of the products obtained based on them. The alkylated products obtained have been tested as plasticizing additives in polyolefin composites.


2018 ◽  
Vol 42 (7) ◽  
pp. 5229-5236 ◽  
Author(s):  
M. Jankowska-Wajda ◽  
R. Kukawka ◽  
M. Smiglak ◽  
H. Maciejewski

We present a simplified method for performing the hydrosilylation reaction in a heterogeneous catalytic system with the use of ionic liquids and microreactor systems.


2017 ◽  
Author(s):  
Jose A. Pomposo

Understanding the miscibility behavior of ionic liquid (IL) / monomer, IL / polymer and IL / nanoparticle mixtures is critical for the use of ILs as green solvents in polymerization processes, and to rationalize recent observations concerning the superior solubility of some proteins in ILs when compared to standard solvents. In this work, the most relevant results obtained in terms of a three-component Flory-Huggins theory concerning the “Extra Solvent Power, ESP” of ILs when compared to traditional non-ionic solvents for monomeric solutes (case I), linear polymers (case II) and globular nanoparticles (case III) are presented. Moreover, useful ESP maps are drawn for the first time for IL mixtures corresponding to case I, II and III. Finally, a potential pathway to improve the miscibility of non-ionic polymers in ILs is also proposed.


2020 ◽  
Author(s):  
Swati Arora ◽  
Julisa Rozon ◽  
Jennifer Laaser

<div>In this work, we investigate the dynamics of ion motion in “doubly-polymerized” ionic liquids (DPILs) in which both charged species of an ionic liquid are covalently linked to the same polymer chains. Broadband dielectric spectroscopy is used to characterize these materials over a broad frequency and temperature range, and their behavior is compared to that of conventional “singly-polymerized” ionic liquids (SPILs) in which only one of the charged species is attached to the polymer chains. Polymerization of the DPIL decreases the bulk ionic conductivity by four orders of magnitude relative to both SPILs. The timescales for local ionic rearrangement are similarly found to be approximately four orders of magnitude slower in the DPILs than in the SPILs, and the DPILs also have a lower static dielectric constant. These results suggest that copolymerization of the ionic monomers affects ion motion on both the bulk and the local scales, with ion pairs serving to form strong physical crosslinks between the polymer chains. This study provides quantitative insight into the energetics and timescales of ion motion that drive the phenomenon of “ion locking” currently under investigation for new classes of organic electronics.</div>


2019 ◽  
Vol 16 (7) ◽  
pp. 550-555
Author(s):  
Dinesh K. Jangid ◽  
Keshav L. Ameta ◽  
Surbhi Dhadda ◽  
Anjali Guleria ◽  
Prakash G. Goswami ◽  
...  

Ionic Liquid assisted efficient synthesis of some 2-aminobenzenethiols has been reported using three different Ionic Liquids (ILs) namely methylimidazolium tetrafluoroborate [MIM]+[BF4]−, methylimidazolium chloride [MIM]+[Cl]− and methylimidazolium nitrate [MIM]+[NO3]−. A comparative study has been carried out for the synthesis of target molecules in the presence and absence of IL, leading to conclusion that maximum yield has been observed with [MIM]+[BF4]−.


2020 ◽  
Vol 16 (5) ◽  
pp. 652-659
Author(s):  
Asiye A. Avan ◽  
Hayati Filik

Background: An Ionic Liquid-based based Dispersive Liquid-Liquid Microextraction (IL-DLLME) method was not applied to preconcentration and determination of bilirubin. Ionic Liquids (ILs) are new chemical compounds. In recent years, Ionic Liquids (ILs) have been employed as alternative solvents to toxic organic solvents. Due to these perfect properties, ILs have already been applied in many analytical extraction processes, presenting high extraction yield and selectivity for analytes. Methods: In this study, IL-DLLME was applied to biological samples (urine and serum) for the spectrophotometric detection of bilirubin. For bilirubin analysis, the full-color development was based on the reaction with periodate in the presence of hydrochloric acid. The high affinity of bilirubin for the ionic liquid phase gave extraction percentages above 98% in 0.3 M HCl solution. Results: Several IL-extraction parameters were optimized and room temperature ionic liquid 1-butyl- 1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and ethanol were used as extraction and disperser solution. The linear range was found in the range of 0.5-6.0 μM (0.3-3.5 μg mL-1) and the limits of detection of the proposed method was 0.5 μM (0.3 μg mL-1). The proposed method was applied for the preconcentration and separation of trace bilirubin in real urine samples. Also, the recoveries for bilirubin in spiked biological samples (urine and serum) were found to be acceptable, between 95-102%. Conclusion: The proposed IL-DLLMEapproach was employed for the enrichment and determination of trace levels of bilirubin in urine samples using NaIO4 as an oxidizing agent and Uv-vis spectrophotometric detection. The periodate oxidation of bilirubin is rapid, effective, selective, and simple to perform. The method contains only HCl, NaOI4, and an anionic surfactant. The method may be useful for economizing in the consumption of reagents in bilirubin determining. The IL-DLLMEmethod ensures a high yield and has a low toxicity no skin sensitization, no mutagenicity and no ecotoxicity in an aquatic environment since only very low quantities of an IL is required. For full-color formation, no any extra auxiliary reagents are required. Besides, the IL-DLLME technique uses a low-cost instrument such as Uv-vis which is present in most of the medical laboratories.


Author(s):  
Dharambir Kashyap ◽  
Ajay Sharma ◽  
Hardeep S. Tuli ◽  
Sandeep Punia ◽  
Anil K. Sharma

2020 ◽  
Vol 6 (2) ◽  
pp. 134-146 ◽  
Author(s):  
Kehkashan Arshad Qamar ◽  
Ahsana Dar Farooq ◽  
Bina S. Siddiqui ◽  
Nurul Kabir ◽  
Sabira Begum

Aims: The aim of the current study was to identify active compound(s) responsible for the antiproliferative effects of O. basilicum and explore their underlying mechanism/s. Background: Plants have been the source of medicines for the treatment of various diseases since ancient times. Ocimum basilicum (Sweet Basil, Bobai Tulsi) has been used in the folk medicine for the treatment of human liver, spleen and stomach cancers. Background: Plants have been the source of medicines for the treatment of various diseases since ancient times. Ocimum basilicum (Sweet Basil, Bobai Tulsi) has been used in the folk medicine for the treatment of human liver, spleen and stomach cancers. Objective: To emphasize the importance of O. basilicum as a potential novel non-toxic alternative to the conventional anticancer therapy. Method: O. basilicum (aerial parts) methanolic extract and fractions were screened against HT-144, MCF-7, NCI-H460 and SF-268 human cancer cell lines using sulforhodamine B assay. The more active Petroleum Ether Insoluble (PEI) fraction was fractionated into six sub-fractions (OB-1 to OB-6). Four pure compounds (3-O-methyl ursolic acid, oleanolic acid, 3-epi-ursolic acid and ursolic acid) were isolated from the more potent sub-fraction OB- 6. Triple channel immunofluorescence microscopy was employed to observe the effects of methanolic extract, PEI fraction, sub-fractions OB-5 and OB-6, 3-epi-ursolic acid and oleanolic acid on the cytoskeleton and nuclei of MCF-7 cells. Result: The methanolic extract and the PEI fraction exhibited selectively greater growth inhibition against MCF-7 cell line (TGI: 56 and 36.2 µg/ml, respectively). By using triple channel immunofluorescence microscopy, it was observed that the methanolic extract, PEI fraction, sub-fraction OB-5 and 3-epi-ursolic acid induced irregular mitotic spindle formation and slowing of mitotic progression in MCF-7 cells while sub-fraction OB-6 induced mitotic arrest in the prophase stage. F-actin aggregation was also visible in PEI fraction, subfraction OB-5 and 3-epi-ursolic acid treated MCF-7 cells. Conclusion: These results emphasize the importance of O. basilicum as a potential novel non-toxic alternative to the conventional anticancer therapy and suggest that it inhibits the growth of MCF-7 cancer cells via multiple mechanisms such as interaction with the microtubules and mitotic spindle apparatus, and F-actin aggregation.


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