15471-17-7Relevant articles and documents
Reversible phase transformation gel-type ionic liquid compounds based on tungstovanadosilicates
Huang, Tianpei,Xie, Zhirong,Wu, Qingyin,Yan, Wenfu
, p. 17 - 22 (2016)
A series of new reversible phase transformation gel-type ionic liquid compounds, [PyPS]5SiW11VO40, [PyPS]7SiW9V3O40, [TEAPS]5SiW11VO40 and [TEAPS]7SiW9V3O40, have been synthesized from two organic ammoniums 1-(3-sulfonic group) propyl-pyridine (PyPS), 1-(3-sulfonic group) propyl-triethylammonium (TEAPS) and vanadium-substituted heteropoly acids H5SiW11VO40 and H7SiW9V3O40. The products can undergo a phase transformation from viscous gel-state to liquid-state below 100 °C, and ionic conductivity up to 10-3 S cm-1 was observed at 110 °C for these gel-type POM-ILs. The relationship between the component elements of the products and their physicochemical property has been studied. Their thermostability was measured using thermogravimetric and differential thermal analysis (TG-DTA), and the result indicates that the less vanadium atoms there are inside the heteropoly anion, the more stable the POM-IL is at high temperature. Cyclic voltammetry is carried out to study their electrochemical properties in organic solution. The potential values of redox waves confirm that the oxidability of these gel-type POM-ILs can be controlled upon changing the number of vanadium atoms in the heteropolyanions.
The synthesis and electrical properties of hybrid gel electrolytes derived from Keggin-type heteropoly acids and 3-(pyridin-1-ium-1-yl)propane-1-sulfonate (PyPs)
Narayanan, Sumaletha,Tong, Xia,Thangadurai, Venkataraman
, p. 102549 - 102556 (2016)
Herein, we report the effect of the proton concentration in polyoxometalates (POMs) upon hybrid formation with ionic liquids (ILs), and their ionic conductivity relationship to optimize their ionic conductivity. The hybrid gels were derived from Keggin-type heteropoly acids containing different proton concentrations, such as H3PW11MoO40, H4PMo11VO40 and H5PMo10V2O40, and 3-(pyridin-1-ium-1-yl)propane-1-sulfonate (PyPs) IL. Elemental C, H, and N analysis was found to be consistent with the theoretical composition within 4% for C and N, whereas H content was found to be slightly higher than the anticipated value, which may be due to potential uptake of water during the sample preparation. 1H and 13C nuclear magnetic resonance and Fourier transform infrared spectroscopy (FTIR) confirmed the presence of functional groups of PyPs in the hybrids. In situ variable temperature powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), electrochemical AC impedance spectroscopy and cyclic voltammetry studies showed excellent thermal (up to ～300 °C) and electrochemical (3 V at room temperature) stability of [PyPs]3PW11MoO40. The structural characterizations confirmed the interaction between the organic cation and Keggin-type inorganic heteropoly anion in the hybrid material. The bulk ionic conductivity of 0.1, 0.01 and 0.0003 S cm-1 at ～90 °C was obtained for [PyPs]3PW11MoO40, [PyPs]4PMo11VO40 and [PyPs]5PMo10V2O40, respectively.
Dual targeting of cholinesterase and amyloid beta with pyridinium/isoquinolium derivatives
Chakravarty, Harapriya,Ju, Yaojun,Chen, Wen-Hua,Tam, Kin Y.
, p. 242 - 255 (2019/12/27)
With the surge in the cases of Alzheimer's disease (AD) over the years, several targets have been explored to curb the disease. Cholinesterases, namely acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), remain to be the available targets that are amendable to currently approved treatments. In this study, a series of novel compounds based on tramiprosate, a highly specific amyloid beta (Aβ) inhibitor, was designed to inhibit AChE, BuChE, and Aβ aggregation. In particular, the addition of a pyridinium/isoquinolinium ring to the tramiprosate moiety (to give compounds 3a–j) led to an increase in the binding affinity for the catalytic active site of cholinesterase, which was hampered by the presence of sulfonic acid. Exclusion of the sulfonic acid moiety led to a novel but effective class of cholinesterase inhibitors (9a–w). in vitro Aβ aggregation inhibition assay indicated that compounds 3a–j, 9e–f, 9i–l, 9q, 9r, 9u–w, and 12 could inhibit over 10% Aβ aggregation at 1 mM concentration. Cholinesterase inhibition assay suggested that compounds 9g, 9h, 9o, and 9q–t exhibit over 70% inhibition on both AChE and BuChE at a concentration of 100 μM. Amongst the designed molecules, compound 9r (ca 18% at 1 mM) showed comparable inhibitory effect on the inhibition of Aβ aggregation with tramiprosate (ca 20% at 1 mM), along with impressive cholinesterase inhibitory potential (AChE IC50 = 13 μM and BuChE IC50 = 12 μM), acceptable toxicity and ability to pass through blood brain barrier, which could be used to ameliorate the phenotypes of AD in preclinical models.
Condensation of 9-fluorenone and phenol using an ionic liquid and a mercapto compound synergistic catalyst
Lei, Yan,Yu, Limei,Shen, Maochang,Luo, Shikang,Gao, Zhanxian
supporting information, p. 15700 - 15705 (2019/10/19)
A series of ionic liquids (ILs) were synthesized and their Hammett acidities (H0) were determined using 4-nitroaniline as the indicator. The relationship among IL's structure, the acid strength, and the catalytic performance in the condensation reaction of 9-fluorenone with phenol was discussed. The effective H0 range of ionic liquids that can catalyse the condensation reaction was obtained. Moreover, the catalysis of the mercapto compound co-catalyst was also systematically studied. According to the analysis of how the structure of the sulfydryl co-catalyst affects the percent conversion of 9-fluorenone and the selectivity of BHPF, a mechanism for the reaction in the IL-thiol cooperative catalytic system was proposed. The present work gave a clear clue to design novel IL catalysts for the synthesis of BHPF.
