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341.
Kramar Ana D. Ilic-Tomic Tatjana R. Lađarević Jelena M. Nikodinovic-Runic Jasmina B. Kostic Mirjana M. 《Cellulose (London, England)》2021,28(13):8771-8784
Cellulose - Halochromic (pH-responsive) material was obtained by dyeing functionalized viscose fabric with a crude extract from Streptomyces sp. strain NP4. The functionalization of the fabric... 相似文献
342.
Dalibor Tatar Jelena Koj
inovi Berislav Markovi Aleksandar Szchenyi Aleksandar Mileti Sndor Balzs Nagy Szilveszter Ziegenheim Imre Szenti Andras Sapi kos Kukovecz Kristijan Dinjar Yushu Tang David Stenzel Gbor Varga Igor Djerdj 《Molecules (Basel, Switzerland)》2021,26(20)
Efficient Lewis-acid-catalyzed direct conversion of aldehydes to 1,2-diketones in the liquid phase was enabled by using newly designed and developed ceria–zirconia-based high-entropy oxides (HEOs) as the actual catalysts. The synergistic effect of various cations incorporated in the same oxide structure (framework) was partially responsible for the efficiency of multicationic materials compared to the corresponding single-cation oxide forms. Furthermore, a clear, linear relationship between the Lewis acidity and the catalytic activity of the HEOs was observed. Due to the developed strategy, exclusively diketone-selective, recyclable, versatile heterogeneous catalytic transformation of aldehydes can be realized under mild reaction conditions. 相似文献
343.
Zdenk Wimmer David aman Jelena Kuldov Didier Desmaële Jean d'Angelo Franoise Goudey-Perrire 《Helvetica chimica acta》1998,81(11):2017-2023
The Michael-type addition reaction was used as a convenient method for the stereocontrolled construction of a new quaternary C-center at position 2 of 2-substituted cyclohexanones (Scheme) with the aim to study the effect of an additional substituent at C(2) in a series of biologically active compounds bearing generally a 2-substituted cyclohexanone moiety. Thus, a new series of compounds consisting of a racemate (RS)- 12 and its enantiomers (S)- and (R)- 12 (ee ≥96% for both enantiomers) was obtained. The Michael adduct derivatives (S)-, (R)-, and (RS)- 12 were subjected to a biological screening using several non-related insect species. 相似文献
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Ismail Ajaj Jasmina Markovski Jelena Marković Maja Jovanović Miloš Milčić Fathi Assaleh Aleksandar Marinković 《Structural chemistry》2014,25(4):1257-1270
The tautomeric equilibria between 2-pyridone and 2-hydroxypyridine forms of methoxy, chloro, and nitro derivatives of 3-cyano-4-(2-, 3-, and 4-substituted phenyl)-6-phenyl-2(1H)-pyridones were evaluated from UV/Vis spectral data. Linear solvation energy relationships of Kamlet–Taft and Catalán-rationalized solvent have influence on tautomeric equilibria. Transmission of substituent effect was analyzed by the Hammett equation. Quantum chemical calculations were performed by density functional theory (B3LYP). The experimental data were interpreted with the aid of time-dependent density functional method. Electron density distribution was analyzed by Bader’s analysis. It was found that substituents of different electronic properties change the extent of conjugation, and affect intramolecular charge transfer character. Theoretical calculations and experimental results gave insight into the influence of the molecular conformation on the transmission of substituent effects, as well as on contribution of different solvent–solute interactions. 相似文献
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