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Unraveling templated-regulated distribution of isolated SiO4 tetrahedra in silicoaluminophosphate zeolites with high-throughput computations

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National Science Review 2022年第9期9卷 19-27页

作者： Yan Li Chao Shi Lin Li Guoju Yang Junyan Li Jun Xu Qinfen Gu Xingxing Wang Ji Han Tianjun Zhang Yi Li Jihong Yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University School of Textile and Clothing Yancheng Institute of Technology State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in Wuhan Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences Australian Synchrotron International Center of Future Science Jilin University

Silicoaluminophosphate(SAPO) zeolites are well-known catalytic materials because of the mild acidity originating from the isolated SiO4tetrahedra in their frameworks. Regulating the distribution of isolated SiO4tetrahedra in SAPO zeolites is formidably challenging because SiO4tetrahedra tend to agglomerate to form Si islands and the isolated SiO4tetrahedra are difficult to determine using conventional characterization techniques. Here we synthesized Si-island-free SAPO-35 zeolites by using N-methylpiperidine as a new template, which exhibited excellent thermal stability compared to conventional SAPO-35 zeolites and a substantially improved methanol-to-olefins catalytic lifetime even comparable to that of commercial SAPO-34 zeolites. More strikingly, with the aid of high-throughput computations on 44 697 structure models combined with various state-of-the-art characterization techniques, for the first time, we reveal that the host–guest interactions between template molecules and SAPO frameworks determine the specific distributions of isolated SiO4tetrahedra, which are responsible for the improvement in the chemical properties of zeolites. Our work provides an insight into the template-based regulation of isolated SiO4tetrahedra in SAPO zeolites, which opens a new avenue in the discovery of promising zeolite catalysts with optimal Si O4distribution.

关键词： acidity computational chemistry heterogeneous catalysis structure–activity relationships zeolites

Tuning Active Metal Atomic Spacing by Filling of Light Atoms and Resulting Reversed Hydrogen Adsorption-Distance Relationship for Efficient Catalysis

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Nano-Micro Letters 2023年第10期15卷 151-162页

作者： Ding Chen Ruihu Lu Ruohan Yu Hongyu Zhao Dulan Wu Youtao Yao Kesong Yu Jiawei Zhu Pengxia Ji Zonghua Pu Zongkui Kou Jun Yu Jinsong Wu Shichun Mu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People’s Republic of China NRC(Nanostructure Research Centre) Wuhan University of TechnologyWuhan 430070People’s Republic of China

Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a ***,we develop a strategy to dilute catalytically active metal interatomic spacing(d_(M-M))with light atoms and discover the unusual adsorption *** example,by elevating the content of boron as interstitial atoms,the atomic spacing of osmium(d_(Os-Os))gradually increases from 2.73 to 2.96?.More importantly,we find that,with the increase in dOs-Os,the hydrogen adsorption-distance relationship is reversed via downshifting d-band states,which breaks the traditional cognition,thereby optimizing the H adsorption and H_2O dissociation on the electrode surface during the catalytic process;this finally leads to a nearly linear increase in hydrogen evolution reaction ***,the maximum dOs-Os of 2.96?presents the optimal HER activity(8 mV@10 mA cm^(-2))in alkaline media as well as suppressed O adsorption and thus promoted *** is believed that this novel atomic-level distance modulation strategy of catalytic sites and the reversed hydrogen adsorption-distance relationship can shew new insights for optimal design of highly efficient catalysts.

关键词： Electrocatalysis DFT calculation Interstitial filling Hydrogen evolution structure–activity relationships

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Discovery of direct inhibitors of Keap1–Nrf2 protein–protein interaction as potential therapeutic and preventive agents

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Acta Pharmaceutica Sinica B 2015年第4期5卷 285-299页

作者： Dhulfiqar Ali Abed Melanie Goldstein Haifa Albanyan Huijuan Jin Longqin Hu Department of Medicinal Chemistry Ernest Mario School of Pharmacy Rutgers The State University of New Jersey School of Pharmaceutical Sciences Shanxi Medical University

The Keap1–Nrf2–ARE pathway is an important antioxidant defense mechanism that protects cells from oxidative stress and the Keap1–Nrf2 protein–protein interaction(PPI) has become an important drug target to upregulate the expression of ARE-controlled cytoprotective oxidative stress response enzymes in the development of therapeutic and preventive agents for a number of diseases and conditions. However, most known Nrf2 activators/ARE inducers are indirect inhibitors of Keap1–Nrf2PPI and they are electrophilic species that act by modifying the sulfhydryl groups of Keap1's cysteine residues. The electrophilicity of these indirect inhibitors may cause "off-target" side effects by reacting with cysteine residues of other important cellular proteins. Efforts have recently been focused on the development of direct inhibitors of Keap1–Nrf2 PPI. This article reviews these recent research efforts including the development of high throughput screening assays, the discovery of peptide and small molecule direct inhibitors, and the biophysical characterization of the binding of these inhibitors to the target Keap1 Kelch domain protein. These non-covalent direct inhibitors of Keap1–Nrf2 PPI could potentially be developed into effective therapeutic or preventive agents for a variety of diseases and conditions.

关键词： Oxidative stress Keap1 Nrf2 Direct inhibitors of protein–protein interaction High throughput screening assays structure–activity relationships X-ray crystallography

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Synthesis and cytotoxic activities of E-resveratrol derivatives

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Chinese Journal of Natural Medicines 2015年第5期13卷 375-382页

作者： HONG Ting JIANG Wei DONG Huai-Ming QIU Sheng-Xiang LU Yu Sino-German Joint Research Institute of Nanchang University Jiangxi Provincial Institute for Food and Drug Control Jiangxi Provincial Engineering Research Center for Drug and Medical Device Quality Chinese Academy of Sciences South China Botanical Garden

The present study was designed to synthesize derivatives of E-resveratrol and evaluate their cytotoxic activity in *** functional groups were conjugated with the phenolic hydroxyl group of E-resveratrol,and the double bond of E-resveratrol was *** in vitro cytotoxicity of the synthetic derivatives was evaluated against three tumor cell lines(A549,LAC,and He La) using the MTT ***-six E-resveratrol derivatives were synthesized and their structures were confirmed by 1H NMR,MS,IR,and elemental *** 1-6,12,15-21,and 23-26 were reported for the first *** them,Compounds 1,2,4,5,and 9-11,showed significant cytotoxicity against tumor cells;especially,Compound 1 showed an IC50 value of 4.38 μmol·L-1 in the A549 cells which was 15-fold more active than E-resveratrol;Compound 9 showed an IC50 value of 1.41 μmol·L-1 in the He La cell line which was 90-fold more active than E-resveratrol,and close to *** structure–activity relationships were also *** 1,2 and 9-11 may serve as potential lead compounds for the discovery of new anticancer drugs.

关键词： E-resveratrol derivatives Synthesis Cytotoxic activity structure–activity relationships

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