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One-Pot Synthesis of Phenytoin Analogs   总被引:1,自引:0,他引:1  
A series of phenytoin analogs (5,5-diphenylimidazolidine-2,4-dione or 5,5-diphenyl-hydantoin) were synthesized in 65–75% yield from the corresponding substituted benzils. The same products were also obtained directly from -hydroxy ketones via one-pot procedure.  相似文献   
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Correction for ‘Click activated protodrugs against cancer increase the therapeutic potential of chemotherapy through local capture and activation’ by Kui Wu et al., Chem. Sci., 2021, 12, 1259–1271, DOI: 10.1039/D0SC06099B.

The authors regret that the reference to the bond-breaking bioorthogonal chemistry, termed ‘click-to-release’ was omitted from the original article. In addition, we would like to include a reference describing the synthesis of compound 1, which is an intermediate to the protodrugs described in the original article. These references are listed below as ref. 1 and 2.The Royal Society of Chemistry apologizes for these errors and any consequent inconvenience to authors and readers.  相似文献   
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Five novel monoazo disperse dyestuffs based on N‐ester‐1,8‐naphthalimide were synthesized. Acenaphthene was nitrated, then oxidized to 4‐nitro‐1,8‐naphthalic anhydride. 4‐Nitro‐1,8‐naphthalic anhydride was reacted with methyl and ethyl glycinate in alcoholic media, followed with reduction. 4‐Amino‐N‐methyl and ethyl glycinate‐1,8‐naphthalimide were obtained. These products were diazotized and coupled with appropriate aromatic amines to give bluish‐red or violet dyestuffs. All intermediates and dyestuffs were purified and characterized by 1H‐NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Dispersion of dyestuffs was prepared in water and applied to polyester fabrics. The dyed fabrics showed that four of the synthesized dyestuffs were suitable for coloring polyester fibers, producing deep bluish red with very good build up properties.  相似文献   
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An RTD[5,λ; v] is a decomposition of the complete symmetric directed multigraph, denoted by λK, into regular tournaments of order 5. In this article we show that an RTD[5,λ; v] exists if and only if (v?1)λ ≡ 0 (mod 2) and v(v?1)λ ≡ 0 (mod 10), except for the impossible case (v,λ) = (15,1). Furthermore, we show that for each v ≡ 1,5 (mod 20), v ≠ 5, there exists a B[5,2; v] which is not RT5-directable. © 1994 John Wiley & Sons, Inc.  相似文献   
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Abstract

Bacterial cellulose (BC) is an extracellular natural polymer produced by many microorganisms and its properties could be tailored via specific fabrication methods and culture conditions. There is a growing interest in BC derived materials due to the main features of BC such as porous fibrous structure, high crystallinity, impressive physico-mechanical properties, and high water content. However, pristine BC lacks some features, limiting its practical use in varied applications. Thus, fabrication of BC composites has been attempted to overcome these constraints. This review article overviews most recent advance in the development of BC composites and their potential in biomedicine including wound dressing, tissue engineering scaffolds, and drug delivery. Special emphasis is placed on the fabrication and applications of BC-containing nanofibrous composites for biomedical usage. It summarizes electrospinning of BC-based nanofibers and their surface modification with an outline on challenges and future perspective.  相似文献   
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Photocatalysis has been known as one of the promising technologies due to its eco-friendly nature. However, the potential application of many photocatalysts is limited owing to their large bandgaps and inefficient use of the solar spectrum. One strategy to overcome this problem is to combine the advantages of heteroatom-containing supports with active metal centers to accurately adjust the structural parameters. Metal nanoparticles (MNPs) and single atom catalysts (SACs) are excellent candidates due to their distinctive coordination environment which enhances photocatalytic activity. Metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and carbon nitride (g-C3N4) have shown great potential as catalyst support for SACs and MNPs. The numerous combinations of organic linkers with various heteroatoms and metal ions provide unique structural characteristics to achieve advanced materials. This review describes the recent advancement of the modified MOFs, COFs and g-C3N4 with SACs and NPs for enhanced photocatalytic applications with emphasis on environmental remediation.  相似文献   
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