Publications by authors named "Yi-Sheng Tan"

Nine new alkaloids, eugeniinalines A-H (-) and (+)-eburnamenine -oxide (), comprising one quinoline, six indole, and two isogranatanine alkaloids, were isolated from the stem-bark extract of the Malayan . The structures and absolute configurations of these alkaloids were established based on the analysis of the spectroscopic data, GIAO NMR calculations, DP4+ probability analysis, TDDFT-ECD method, and X-ray diffraction analysis. Eugeniinaline A () represents a new pentacyclic quinoline alkaloid with a 6/6/5/6/7 ring system.

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Eugeniifoline (), a pentacyclic indole alkaloid with a five-membered ring E, was isolated for the first time as a natural product from the stem-bark extract of . Eugeniifoline () was previously reported as a synthetic product from a diversity-enhanced extract, but with the configuration at C-21 reported as (). The configuration at C-21 was revised to as shown in , based on the NOE data, GIAO NMR calculations, and DP4+ probability analysis, as well as the TDDFT-ECD method.

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The synthesis of dimethoxymethane (DMM) from direct oxidation of dimethyl ether (DME) is a green and competitive route with good atomic economy and low carbon emission and is also an urgent need. In this work, biomass-based carbon-supported sulfate catalysts were designed and prepared for the efficient synthesis of DMM from DME oxidation. The prepared carbon support from cellulose displayed much larger specific surface area and a developed microporous structure, which effectively benefited a high dispersion of sulfate components, leading to mainly weak acid sites and more oxygen functional groups on the catalyst surface.

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To substitute for petroleum, Fischer-Tropsch synthesis (FTS) is an environmentally benign process to produce synthetic diesel (n-paraffin) from syngas. Industrially, the synthetic gasoline (iso-paraffin) can be produced with a FTS process followed by isomerization and hydrocracking processes over solid-acid catalysts. Herein, we demonstrate a cobalt nano-catalyst synthesized by physical-sputtering method that the metallic cobalt nano-particles homogeneously disperse on the H-ZSM5 zeolite support with weak Metal-Support Interactions (MSI).

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NO(x) emission control of lean-burn engines is one of the great challenges in the world. Herein, the MnOx model catalysts with the different calcination temperatures were synthesized to investigate their NO adsorbability for lean-burn exhausts. The transformation from (β-)MnO₂ to (α-)Mn₂O₃ following the increased calcination temperatures was evidenced from the viewpoint of the local atomic level.

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