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By using hologram quantitative structure-activity relationship (HQSAR) and comparative molecular field analysis (CoMFA) methods, the relationships between the structures of 49 gallic acid derivatives and their analgesic activity have been investigated to yield statistically reliable models with considerable predictive power. The best HQSAR model was generated using atoms, bond and connectivity as fragment distinction parameters and fragment size 5-7 from a hologram length of 307 with 3 components. High conventional r2 (r2 = 0.825) and cross-validation r2 (r2(cv) = 0.726) values were obtained. CoMFA analyses varying lattice size and location, grid spacing, probe charges and using, Tripos standard and Indicator force field were performed. The best model was developed with 4 components using sp3-hybridized carbon atom with +1.0 charge as probe, grid spacing (2 A), lattice offset (1.0, 3.0, -2.5). The CoMFA model showed a conventional correlation coefficient r2 of 0.889 and across-validation r2(cv) equals to 0.633. The robustness and predictive ability of the HQSAR and CoMFA models have been validated by means of an external test set. The results indicate that both models possess high statistical quality in the prediction of analgesic potency of novel gallic acid analogs. 相似文献
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Two molecular imprinting polymer (MIP) monolithic columns with (S)-(-)-1,1'-bi-2-naphthol and (R)-(+)-5,5',6,6',7,7',8,8'-octahydro-1,1'-bi-2-naphthol as the templating molecules, respectively, have been prepared by in situ polymerization using 4-vinylpyridine and ethylene dimethacrylate as functional monomer and cross-linker, respectively. The columns with good flow-through properties were obtained by changing the molar ratio of the functional monomer and the template molecule. The effects of mobile-phase composition on separation of enantiomers were systematically investigated. The results indicate that hydrophobic interaction in aqueous solution and hydrogen-bonding interaction in ACN between the enantiomers and polymers could play important roles in the retention and resolution. The effects of chromatographic conditions, such as flow rate, column temperature, sample loading, on the enantioseparation were also studied. Further, these two MIP columns show a cross-reactivity. 相似文献
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Xiaona Wen Yu-Chuan Ou Galina Bogatcheva Giju Thomas Anita Mahadevan-Jansen Bhuminder Singh Eugene C. Lin Rizia Bardhan 《Chemical science》2020,11(36):9863
Rapid and accurate response to targeted therapies is critical to differentiate tumors that are resistant to treatment early in the regimen. In this work, we demonstrate a rapid, noninvasive, and label-free approach to evaluate treatment response to molecular inhibitors in breast cancer (BC) cells with Raman spectroscopy (RS). Metabolic reprogramming in BC was probed with RS and multivariate analysis was applied to classify the cells into responsive or nonresponsive groups as a function of drug dosage, drug type, and cell type. Metabolites identified with RS were then validated with mass spectrometry (MS). We treated triple-negative BC cells with Trametinib, an inhibitor of the extracellular-signal-regulated kinase (ERK) pathway. Changes measured with both RS and MS corresponding to membrane phospholipids, amino acids, lipids and fatty acids indicated that these BC cells were responsive to treatment. Comparatively, minimal metabolic changes were observed post-treatment with Alpelisib, an inhibitor of the mammalian target of rapamycin (mTOR) pathway, indicating treatment resistance. These findings were corroborated with cell viability assay and immunoblotting. We also showed estrogen receptor-positive MCF-7 cells were nonresponsive to Trametinib with minimal metabolic and viability changes. Our findings support that oncometabolites identified with RS will ultimately enable rapid drug screening in patients ensuring patients receive the most effective treatment at the earliest time point.Rapid and accurate response to targeted therapies is critical to differentiate tumors that are resistant to treatment early in the regimen. 相似文献
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本文合成了部分烷基化三氟乙酰化的β-环糊精手性固定相(DP-TFA-β-CD),并把它与普通聚硅氧烷OV-7混合制备出了柱效高、热稳定性好的手性石英毛细管柱。与直接涂DP-TFA-β-CD相比,混合固定相能在较短分析时间内对卤代烃、醇、酯、γ-内酯、胺等对映体有更好的拆分。 相似文献
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Carbonylation of benzyl halides to phenylacetic acid was studied in a two-phase system with iron pentacarbonyl as the catalyst precursor. The solutions consisted of a benzyl halide and iron pentacarbonyl in benzene and tetrabutylammonium hydrogen sulfate in aqueous sodium hydroxide. Stirring under carbon monoxide readily produced phenylacetic salts in aqueous phase which were then acidified and extracted with ether. The yields of phenylacetic acid from benzyl iodide and from benzyl bromide were similar at a evel of about 50percnt;, that of the latter being higher by 1%. The yield from benzyl chloride was far less, at a level of only 21%. The rate as studied with gas chromatography was found to decrease in the order benzyl iodide>benzyl bromide>benzyl chloride. 相似文献
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多硝基多氨基三唑类衍生物作为含能材料,具有高氮、致密、钝感等优点。本文通过3-氨基-1,2,4-三唑和三硝基三氯苯的缩合,再经过三唑碳原子上的硝化反应和芳环上的氨化反应,合成并鉴定了标题化合物。 相似文献