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Prof. Dr. Manabu Yamada Fumiya Uemura Dr. Uma Maheswara Rao Kunda Prof. Dr. Takenori Tanno Prof. Dr. Hiroshi Katagiri Prof. Dr. Fumio Hamada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(38):8393-8399
Alkanes composed of C−C and C−H show a low electric polarization, and therefore, there is only very weak interaction between alkanes and adsorbents. Thus, it is difficult to separate a specific alkane from a mixture of alkanes by adsorption. Here, two activated “channel-like” crystals generated from brominated thiacalix[4]arene propyl ethers, which adopt 1,3-alternate and partial cone conformations, recognize specific alkane vapors depending on alkane-shape and -size, sorting in three-type alkane guests such as linear, branched, and cyclic alkanes. Two activated crystals, which are prepared by removal of solvent upon heating under reduced pressure, incorporate branched and/or cyclic alkane vapors by a unique “gate-opening” mechanism via a crystal transformation in the process. Linear alkane vapors do not trigger gate opening and are not taken up by the activated crystals. The shape and size molecular-recognition properties of the activated crystals promises considerable usefulness for the separation of linear, branched, and cyclic alkanes. 相似文献
14.
Zixin Chen Dr. Min Chen Dr. Yunfeng Cheng Prof. Toshiyuki Kowada Dr. Jinghang Xie Dr. Xianchuang Zheng Prof. Jianghong Rao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(8):3298-3305
The condensation reaction between 6-hydroxy-2-cyanobenzothiazole (CBT) and cysteine has been shown for various applications such as site-specific protein labelling and in vivo cancer imaging. This report further expands the substrate scope of this reaction by varying the substituents on aromatic nitriles and amino thiols and testing their reactivity and ability to form nanoparticles for cell imaging. The structure–activity relationship study leads to the identification of the minimum structural requirement for the macrocyclization and assembly process in forming nanoparticles. One of the scaffolds made of 2-pyrimidinecarbonitrile and cysteine joined by a benzyl linker was applied to design fluorescent probes for imaging caspase-3/7 and β-galactosidase activity in live cells. These results demonstrate the generality of this system for imaging hydrolytic enzymes. 相似文献
15.
Ding Wenwen He Yongjia Lu Linnu Rao Meijuan Wang Fazhou 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2009-2018
Journal of Thermal Analysis and Calorimetry - The present task is to investigate the influence of iron on the mineral composition and microstructure of the phase Q (C20A13M3S3, in the text below... 相似文献
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Tingke Rao Prof. Maria Luisa Saladino Prof. Yuanxing Fang Prof. Xinchen Wang Dr. Cristina Giordano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(72):16676-16682
A versatile synthetic strategy for the preparation of multimetallic oxynitrides has been designed and here exemplarily discussed considering the preparation of nanoscaled zinc–gallium oxynitrides and zinc–gallium–indium oxynitrides, two important photocatalysts of new generation, which proved to be active in key energy related processes from pollutant decomposition to overall water splitting. The synthesis presented here allows the preparation of small nanoparticles (less than 20 nm in average diameter), well-defined in size and shape, yet highly crystalline and with the highest surface area reported so far (up to 80 m2 g−1). X-ray diffraction studies show that the final material is not a mixture of single oxides but a distinctive compound. The photocatalytic properties of the oxynitrides have been tested towards the decomposition of an organic dye (as a model reaction for the decomposition of air pollutants), showing better photocatalytic performances than the corresponding pure phases (reaction constant 0.22 h−1), whereas almost no reaction was observed in absence of catalyst or in the dark. The photocatalysts have been also tested for H2 evolution (semi-reaction of the water splitting process) with results comparable to the best literature values but leaving room for further improvement. 相似文献
17.
Durga Rao B. V. Sreenivasulu R. Basaveswara Rao M. V. 《Russian Journal of General Chemistry》2019,89(10):2115-2120
Russian Journal of General Chemistry - A series of isoxazole-thiadiazole linked carbazole derivatives 12a–12j are synthesized and their chemical structures confirmed by 1H and 13C NMR and... 相似文献
18.
Eric C. Chi Liuyi Hu Arvind K. Saibaba Arvind U. K. Rao 《Journal of computational and graphical statistics》2019,28(1):36-47
We consider the problem of performing matrix completion with side information on row-by-row and column-by-column similarities. We build upon recent proposals for matrix estimation with smoothness constraints with respect to row and column graphs. We present a novel iterative procedure for directly minimizing an information criterion to select an appropriate amount of row and column smoothing, namely, to perform model selection. We also discuss how to exploit the special structure of the problem to scale up the estimation and model selection procedure via the Hutchinson estimator, combined with a stochastic Quasi-Newton approach. Supplementary material for this article is available online. 相似文献
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Sreelakshmi Poola Saichaithanya Nagaripati Sreekanth Tellamekala Venkataramaiah Chintha Peddanna Kotha Jayavardhana Rao Yagani 《合成通讯》2020,50(17):2655-2672
Abstract An efficient method for the synthesis of α-aminophosphonate derivatives has been developed with different functional groups under catalyst and solvent free conditions at room temperature in both conventional and ultrasonication methods. Ultrasonication method offers excellent yields within shorter reaction times. All the title compounds 4a–l were tested for their antibacterial, antiviral activity using Gram-positive bacteria (Staphylococcus aureus, and Bacillus subtilis), Gram-negative bacteria (Klebsiella pneumoniae and Escherichia coli) and NDV infected embryonated eggs (in ovo) and NDV infected BHK-21 cell lines (in vitro) respectively. Besides, molecular docking studies were also carried out to the title compounds against Hemagglutinin-neuramidase enzyme to determine the therapeutic binding efficacy of the ligands synthesized. The results indicated that, among the title compounds, compounds such as 4f, 4l, 4k, 4b, 4i and 4h have shown high content of antibacterial and antiviral activity than the rest of the compounds and the level activity was high when compared to the standard, ribavirin. Based on the results, it is concluded that, the reported α-aminophosphonates will open new vistas and stands as a new generation of antiviral and antibacterial drug candidates in future. 相似文献
20.
Jilloju Parameshwara Chary Persoons Leentje Kurapati Sathish Kumar Schols Dominique De Jonghe Steven Daelemans Dirk Vedula Rajeswar Rao 《Molecular diversity》2022,26(3):1357-1371
A new series of (?±)-(3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-phenyl-6,7-dihydro-5H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-7-yl)(phenyl)methanones were efficiently synthesized starting from 4-amino-5-hydrazinyl-4H-1,2,4-triazole-3-thiol 1, acetyl acetone 2, various aromatic and heterocyclic aldehydes 3 and phenacyl bromides 4. All the newly synthesized compounds were tested for their antiviral and antitumoral activity. It was shown that subtle structural variations on the phenyl moiety allowed to tune biological properties toward antiviral or antitumoral activity. Mode-of-action studies revealed that the antitumoral activity was due to inhibition of tubulin polymerization.
Graphic abstract 相似文献