Degn McCann (selfcoast14)
Gout is a common inflammatory arthritis associated with various comorbidities, such as cardiovascular disease and metabolic syndrome. Xanthine oxidase inhibitors (XOIs) have emerged as effective substances to control gout. Much attention has been given to the search for natural XOIs. In this study, a molecular database of natural XOIs was created for modeling purposes. Quantitative structure-activity relationship models were developed by combining various machine learning approaches and three descriptor pools. The models revealed several features of XOIs, including hydrophobicity and steric molecular structures. Experimental results showed the xanthine oxidase (XO) inhibitory activity of predicted compounds. U0126 Vanillic acid was identified as a promising new XOI candidate, with an IC50 of 0.593 μg mL-1. The functions of hydrogen bonds and hydrophobic interactions in XO activity inhibition were confirmed by molecular docking. This study fills knowledge gaps pertaining to the discovery of natural XOIs and to the interaction mechanisms between XOIs and XO.We have studied the decomposition and isomerization of furfural in the gas phase using quantum chemical and statistical reaction rate theory techniques. This work uncovers a variety of new reaction channels in furfural pyrolysis that lead to formation of the experimentally observed products, including CO2, which was previously unexplained. In addition to the known mechanism for furan + CO production, furfural is shown to isomerize directly to 2-pyrone, with a barrier height of 69 kcal mol-1, from where it can decompose to vinylketene + CO (highest barrier of 65 kcal mol-1) or to CO2 + 1,3-cyclobutadiene (highest barrier of 66 kcal mol-1). Alternative pathways to vinylketene + CO and 4-pyrone are also described. An RRKM theory/master equation model is developed to describe reactions on the C5O2H4 surface and used to simulate the decomposition kinetics of furfural and 2-pyrone. For both molecules, decomposition at 1400-2100 K is dominated by the formation of furan + CO, which represents around 75% of the total products, compared to around 19% and 6% for vinylketene + CO and total CO2, respectively. The model also predicts significant formation of stabilized 2-pyrone under these conditions. Rate coefficient expressions are reported as a function of both temperature and pressure for the main decomposition and isomerization channels identified in the pyrolysis of furfural and 2-pyrone, to facilitate detailed chemical kinetic modelling of these important oxygenated hydrocarbons.An effective electrochemical immunosensor for detecting the liver cancer biomarker was developed based on the hedgehog-like Bi2S3 nanostructure, which was synthesized using novel CTAB-trimellitic acid as a composite soft template and thiourea as the sulfur source by a simple hydrothermal method with 20-fold sensitivity enhancement and one order of magnitude increase of linear range. The electrochemical immunosensor presented excellent performance, and could be applied to detect the cancer biomarker in clinical serum samples.Selective oxidation of propene to acrolein and acrylic acid has been applied in industry for many years. In this work, the density functional theory plus U (DFT+U) method was performed to study the hydrogen abstraction of propene on the MoO3(010) surface. From the most stable chemisorbed propene (di-σ propene), the allyl intermediate is difficult to produce on a perfect MoO3(010) surface because of the high barrier. In general, the barriers of the second hydrogen abstraction are much lower than those of the first one. The conclusion from our slab model calculations is consistent with the experimental results. It is found that the (3 + 2) mechanism exhibits lower barriers than the (5 + 2) mechanism. Oxygen defects facilitate the first dehydrogenation significantly, and π-allyl converts to σ-allyl favorably on defects, in agreement with a previous experimental study. The present study i