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71.
《Arabian Journal of Chemistry》2022,15(9):104109
Medicinal chemistry investigators have isolated and synthesized benzoflavone analogues with diverse bioactivities including enzyme inhibitory activity, central nervous system (CNS) activity, anti-inflammatory activity, anti-microorganism activity, hypoglycemic activity, and receptor modulating potential. SAR (Structure-Activity Relationship) studies have been conducted extensively and plenty of benzoflavone analogues have been prepared for potential targets. Herein, we review the pharmacology properties and SAR for benzoflavone analogues, and provide a brief summarization of synthetic strategies, wishing to give perspective on the research and development of benzoflavone derivatives. 相似文献
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《Arabian Journal of Chemistry》2022,15(7):103906
Environmental pollution and energy shortage are substantial fears to the modern world's long-term sustainability. Water splitting is an essential technique for eco - friendly and sustainable energy storage, as well as a pollution-free method to produce hydrogen. In this regards Metal–organic frameworks have emerged as the most competent multifunctional materials in recent times, due to its large surface areas, adjustable permeability, easy compositional alteration, and capability for usage as precursors with a wide range of morphological forms. Further, MOF-derived carbon-based nanomaterials also offer significant benefits in terms of tunable morphological features and hierarchical permeability, as well as ease of functionalization, making them extremely effective as catalysts or catalysts supports for a wide variety of important reactions. Recent developments in carbon-based MOFs as catalysts for overall water splitting are discussed in this review. We explore how MOFs and carbon-based MOFs might well be beneficial, as well as which methods should be explored for future development. We divided our review into two sections: photocatalytic and electrocatalytic water splitting, and we gathered published literature on carbon-based MOFs materials for their outstanding activity, offers helpful methods for catalysts design and analysis, as well as difficulties This study highlights the developments in MOF derived materials as photo and electro catalysts by explaining respective approaches for their use in overall water splitting. 相似文献
76.
作者研究了相对宽度Kn(W2α(T), MW2β(T), L2(T)), T=[0,2π], 确定了使等式Kn(W2α(T), MW2β(T), L2(T))=dn(W2α(T), L2(T))成立的最小M值, 得到了相对宽度Kn(W2α(T), W2α(T), Lq(T))的渐近阶, 其中α≥β>0, 1≤q≤∞, Kn(., ., Lq(T)) 和 dn(., Lq(T))分别表示Kolmogorov意义下Lq(T)尺度下的相对宽度和宽度, MWpα(T), 1≤ p≤∞, 表示有如下卷积表达式的2π 周期函数类, f(t)=c+(Bα* g)(t),c∈ R, Bα*g 表示 Bα 和g 的卷积, g∈Lp(T) 满足∫02πg(τ)dτ=0 和||g||p≤M, Bα∈ L1(T) 有如下Fourier展开: Bα(t)=1/2π∑' k∈ Z(ik)-αeikt,∑'表示去掉 k=0的项. 相似文献
77.
Xiao Ming Zha Fei Ran Zhang Jia Qi Shan Yi Hua Zhang Jun O. Liu Hong Bin Sun 《中国化学快报》2010,21(9):1087-1090
<正>Solasodine 11 is a steroidal alkaloid with various biological activities.Herein,8 novel solasodine derivatives were synthesized and their effect on prostate cancer cell proliferation was assessed in vitro.Significant improvement in antiproliferative activity was achieved among some of the synthetic analogs.In particular,19 exhibited the most potent inhibitory effect against the proliferation of PC-3 cell line(IC_(50) = 3.91μmol/L). 相似文献
78.
甲壳质、甲壳胺衍生物保护的贵金属胶体 总被引:8,自引:0,他引:8
<正> 高分子保护金属胶体是近年来金属催化剂领域中引人注目的研究课题。它除了具有负载型金属催化剂的优点外,还具备下列新优点:a.胶体分散体系可形成“均相”溶液;b.保护高分子可以屏蔽胶体催化剂,减小毒物或空气的不良影响;c.胶体溶液的透光性能比颗粒要好得多,由此最近高分子保护金属胶体常被用于光化学研究中的催化剂;d.高分子保护金属胶体与普通金属胶体相比较,不仅具有较稳定的特点,而且尺寸小(1—10nm)、分布窄,表现出极高的催化活性和选择性;e.保护高分子对金属的修饰作用,可 相似文献
79.
Summary Methylphenylmalonic acid was decarboxylated to yield 2-phenylpropionic acid with an optical induction of 36% ee using catalytic amounts of CuCl and an excess of (+)-cinchonine in acetonitril. Methylphenylmalonic acid hemiethylester gave ethyl 2-phenylpropionate of 20% ee with catalytic amounts of CuCl and (+)-cinchonine, respectively. The tetraethylammonium salt of methylphenylmalonic acid could be decarboxylated in the presence of CuCl, (+)-cinchonine, and chiral carboxylic acids, the best result of 27% ee being obtained with malic acid. 相似文献
80.
Igor B. Sivaev Zoya A. Starikova Vladimir I. Bregadze 《Journal of organometallic chemistry》2005,690(11):2790-2795
Reactions of decaborane with various aldehydes in alkaline media were studied. The reactions with HCOH and 2-MeOC6H4CHO give the corresponding arachno-carboranes [6-R-arachno-CB9H13]− (R = H, C6H4-2-OMe), whereas the reactions with C6H5CHO, 4-BrC6H4CHO, 4-MeCONHC6H4CHO, and 2-SC4H3CHO result in the nido-carboranes [6-R-nido-CB9H11]− (R = C6H5, C6H4-4-Br, C6H4-4-NHCOMe, 2-SC4H3). Both the arachno- and nido-carboranes can be easily oxidized with elemental iodine in an alkaline aqueous solution giving the corresponding closo-derivatives [2-R-closo-2-CB9H9]−. These closo-2-isomers, under heating in solution, undergo rearrangement to more thermodynamically favorable closo-1-isomers [1-R-closo-1-CB9H9]−. The structure of (Bu4N)[1-(4-BrC6H4)-1-CB9H9] was determined using single crystal X-ray diffraction. 相似文献