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Synthesis and Biological Evaluation of Entecavir 4＇-Ester Derivatives

Chemical Research in Chinese Universities 2014年第5期30卷 749-754页

作者： FENG Deri LIU Jiaan LIANG Shuang WANG Yanyan XU Youjun School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 P. R. China

Entecavir can significantly inhibit the replication of HBV-DNA, reduce the HBV-DNA level in blood se- rum. But suffering from low oral bioavailability, entecavir has low intestinal membrane permeability and poor meta- bolic stability. In this study, 12 different derivatives of entecavir 4＇-ester were regioselectively synthesized and their apical-to-basolateral permeabilities across Caco-2 cells and HBV-DNA inhibitory efficacies were evaluated. Most of the compounds showed high permeabilities across Caco-2 cells compared with entecavir, compounds 5b and 5e also exhibited comparable anti-HBV activities with that of entecavir, especially.

关键词： Entecavir Anti-HBV activity Intestinal membrane permeability

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Construction of Angularly Fused Tricyclic Compounds via Photo-induced Radical Cascade Cyclization

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Chinese Journal of Chemistry 2023年第19期41卷 2502-2506页

作者： Mengqin Hu Wei Cao Zhen Wang Yan Hao Ganxing Huang Yuqiao Zhou Song Qin Shaomin Fu Bo Liu Key Laboratory of Green Chemistry&technology of Ministry of Education College of ChemistrySichuan UniversityChengduSichuan610064 China

Photo-induced electron transfer (PET) of silyl enol ethers has been employed to synthesize several fused ring systems. However, the method has limited applicability due to its narrow substrate scope, low product yields, unsatisfactory stereo- and regioselectivity. Herein, we report a PET-triggered cascade reaction of silyl enolates that leads to the formation of angularly fused tricyclic scaffolds. The reaction exhibits broad substrate scope and excellent stereoselectivity. The regio- and stereoselectivity of this cascade reaction is elucidated via DFT calculation and conformational analysis.

关键词： Cyclization Radical Tricyclic compounds Photocatalysis Enols Fused-ring systems Domino reactions Regioselectivity

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PI3K/Akt/mTOR signaling as Targets for Developing Anticancer Agents from Marine Organisms

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Journal of Ocean University of china 2021年第3期20卷 688-694页

作者： GUO Mingyue ZUO Ling QIAO Gan LIU Minghua CAO Shousong LIN Xiukun department of Pharmacology School of PharmacySouthwest Medical UniversityLuzhou 646000China Central Nervous System Drug Key Laboratory of sichuan province Luzhou 646000China

The PI3K/Akt/mTOR signaling pathway is one of the most frequently dysregulated pathways in *** the PI3K-mediated pathway has been an important strategy for developing novel anticancer *** the past decades,more than 40 inhibitors of the PI3K/Akt/mTOR pathway have been developed at different clinical ***,everolimus,idelalisib,and copanlisib have been approved for clinical use by the Food and Drug Administration of the United States(FDA).However,the toxic-ity and drug resistance limit their efficiency in the *** compounds with greater potency and selectivity,as well as im-proved therapeutic indices with reduced toxicity,are clearly *** the past three decades,a lot of bioactive ingredients with anticancer effects by affecting the PI3K-mediated pathways have been found from marine *** the present mini-review,anticancer compounds from marine source that target the PI3K/Akt/mTOR signaling were *** molecular entities and their modes of action were *** marine compounds targeting special factors of the PI3K/Akt/mTOR were highlighted.

关键词： marine organisms PI3K/Akt/mTOR pathway anticancer activity

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Reliable resource allocation with RF fingerprinting authentication in secure IoT networks

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science china(Information sciences) 2022年第7期65卷 51-66页

作者： Weiwei WU Su HU Di LIN Gang WU National Key Laboratory of science and technology on Communications University of Electronic Science and Technology of China

The unprecedented growth of the Internet of Things(Io T) has led to a huge amount of wireless resource consumption in a network. Due to limited wireless resources, a network can only guarantee the quality of service(QoS) of authenticated users rather than that of all users. By acknowledging this limitation,we realise that user authentication would be a big issue in Io T networks. Although traditional authentication methods can enhance network security to a certain extent, their vulnerability to malicious attacks and the relevant complicated computations restrict Io T deployments. In this paper, a radio frequency(RF)fingerprinting based authentication scheme is proposed under the architecture of convolutional neural network(CNN). It can effectively prevent unauthenticated users from consuming valuable wireless resources and significantly improve QoS performance for legitimate users. By solving an NP-hard optimization problem with the objective of minimizing efficient energy density, we demonstrate an approximate optimal resource allocation scheme in consideration of an RF-fingerprinting based authentication process. The analytic results show that our proposed scheme can dramatically reduce the efficient energy density compared with traditional cryptography based authentication schemes.

关键词： user authentication Internet of things convolutional neural network RF fingerprinting NP-hard optimization problem

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A high-quality-factor ultra-narrowband perfect metamaterial absorber based on monolayer molybdenum disulfide

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Chinese Physics B 2022年第3期31卷 571-574页

作者： Liying Jiang Yingting Yi Yijun Tang Zhiyou Li Zao Yi Li Liu Xifang Chen Ronghua Jian Pinghui Wu Peiguang Yan Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang 621010China College of Physics and Electronics Central South UniversityChangsha 410083China College of science Zhejiang University of TechnologyHangzhou 310023China School of science Huzhou UniversityHuzhou 313000China College of Physics and Information Engineering Quanzhou Normal UniversityQuanzhou 362000China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

In order to significantly improve the absorption efficiency of monolayer molybdenum disulfide(M-MoS_(2)), an ultranarrowband M-MoS_(2)metamaterial absorber was obtained through theoretical analysis and numerical calculation using the finite difference time domain method. The physical mechanism can be better analyzed through critical coupling and guided mode resonance. Its absorption rate at λ = 806.41 nm is as high as 99.8%, which is more than 12 times that of bare MMoS_(2). From the simulation results, adjusting the geometric parameters of the structure can control the resonant wavelength range of the M-MoS_(2). In addition, we also found that the maximum quality factor is 1256.8. The numerical result shows that the design provides new possibilities for ultra-narrowband M-MoS_(2) perfect absorbers in the near-infrared *** results of this work indicate that the designed structure has excellent prospects for application in wavelength-selective photoluminescence and photodetection.

关键词： metamaterials ultra-narrowband high quality factor critical coupling

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Medium-range order endows a bulk metallic glass with enhanced tensile ductility

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Journal of Materials science & technology 2023年第28期159卷 10-20页

作者： sinan Liu Weixia Dong Zhiqiang Ren Jiacheng Ge Shu Fu Zhenduo Wu Jing Wu Yu Lou Wentao Zhang Huaican Chen Wen Yin Yang Ren Joerg Neuefeind Zesheng You Ying Liu Xun-Li Wang si Lan Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China department for Physics City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong SARChina City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China City University of Hong Kong(Dongguan) Dongguan 523000China Cryo-TEM center Southern University of Science and TechnologyShenzhen 518055China Spallation Neutron Source science Center Institute of High Energy Physics(IHEP)Chinese Academy of Sciences(CAS)Dongguan 523808China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering science and technology 1 Zhongziyuan RoadDalangDongguan 523803China Chemical and Engineering Materials Division Oak Ridge National LaboratoryOak RidgeTennessee37831USA

Developing ductile bulk metallic glasses(BMGs)can benefit from an in-depth understanding of the structure-property relation during plastic ***,endowing BMGs with tensile ductility in BMGs needs to reveal the response of critical structure units during ***,we report the experimental results of an in-situ synchrotron high-energy X-ray study of a Zr-based BMG under uniaxial tension after preprocessing by canning compression of the three-dimensional compressive stress *** is revealed that the canning-compressed BMG(CC-BMG)sample has better tensile ductility and higher ultimate strength than the as-cast sample,which possesses heterogeneous and loosely packed local struc-tures on medium-range *** experimental results revealed two stages of plastic deformation in the CC-BMGs compared with one stage of plastic deformation in the as-cast ***,the shift in the first sharp diffraction peak along the tension direction for the canning-compressed sample is substan-tially more pronounced than that of the as-cast ***,the real-space analysis illustrates a competition mechanism between the 2-atom and 3-atom connection modes on medium-range order during the plastic deformation of the ***,the ordering on the medium-range scale de-creases in the first plastic deformation stage but increases in the second plastic deformation ***-fore,a structural crossover phenomenon occurs in the CC-BMG during plastic *** results demonstrate a structure-property correlation for the CC-BMGs of heterogeneous medium-range ordered structures,which may be beneficial for endowing BMGs with ductility based on medium-range order engineering techniques.

关键词： Bulk metallic glass Medium-range order Tensile ductility Structure-property relation

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