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1.
Michael A. Pudovik Lyudmila Kibardina Alexey Trifonov Alexey Dobrynin Sergei Katsyuba Alexander Burilov 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):120-126
New O-phosphorylated pyridoxal derivatives have been synthesized through the reaction of azomethines with РV acid chlorides. 2-Chloro-2-thioxo-5,5-dimethyl-1,3,2-dioxaphosphinanes and diethylchlorothiophosphate have been employed as phosphorylating agents. Regardless of the nature of the phosphorylating agent, the reaction is regioselective at phenolic hydroxyl group. The structure of final products is determined by the nature of the substituent at the nitrogen atom. If R is alkyl or cycloalkyl group, the products of the reaction represent phosphorylated pyridoxal imines, whereas phosphorylated furopyridines are formed in the case R is aryl substituent. 相似文献
2.
AbstractThe reaction between glutathionylcobalamin (GSCbl), a complex of Co(III)-cobalamin with glutathione, and selenocysteine (Sec) was investigated using ultraviolet-visible (UV–vis) spectroscopy. The interaction results in the formation of cob(II)alamin and proceeds via two pathways: (i) a rapid formation of complex between GSCbl and Sec followed by the rate-determining substitution of glutathionyl-ligand by Sec and rapid electron-transfer from Se-atom to Co(III)-ion and (ii) a nucleophilic attack of Co(III)-S bond by Sec. 相似文献
3.
Transport in Porous Media - A numerical model is investigated representing counter-current spontaneous imbibition of water to displace oil or gas from a core plug. The model is based on mass and... 相似文献
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5.
Gated Channels and Selectivity Tuning of CO2 over N2 Sorption by Post‐Synthetic Modification of a UiO‐66‐Type Metal–Organic Framework 下载免费PDF全文
Alexander Kronast Sebastian Eckstein Dr. Peter T. Altenbuchner Dr. Konrad Hindelang Dr. Sergei I. Vagin Prof. Dr. Bernhard Rieger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12800-12807
The highly porous and stable metal–organic framework (MOF) UiO‐66 was altered using post‐synthetic modifications (PSMs). Prefunctionalization allowed the introduction of carbon double bonds into the framework through a four‐step synthesis from 2‐bromo‐1,4‐benzenedicarboxylic acid; the organic linker 2‐allyl‐1,4‐benzenedicarboxylic acid was obtained. The corresponding functionalized MOF (UiO‐66‐allyl) served as a platform for further PSMs. From UiO‐66‐allyl, epoxy, dibromide, thioether, diamine, and amino alcohol functionalities were synthesized. The abilities of these compounds to adsorb CO2 and N2 were compared, which revealed the structure–selectivity correlations. All synthesized MOFs showed profound thermal stability together with an increased ability for selective CO2 uptake and molecular gate functionalities at low temperatures. 相似文献
6.
Sergei V. Chapyshev Denis V. Korchagin Paulo Costa Wolfram Sander 《Magnetic resonance in chemistry : MRC》2022,60(8):829-835
The first X-band EPR spectrum containing only non-overlapping signals of septet pyridyl-2,4,6-trinitrene and triplet pyridylnitrenes is reported. This spectrum was recorded after photolysis of 2,4,6-triazidopyridine in solid argon at 5 K. The zero-field splitting (ZFS) parameters of this trinitrene as well as of intermediate triplet mononitrenes and quintet dinitrenes formed at early stages of the photolysis were determined using the combination of modern computer line-shape spectral simulations and density functional theory (DFT) calculations. It was found that septet pyridyl-2,4,6-trinitrene has the record negative parameter DS = −0.1031 cm−1 among all known to date septet pyridyl-2,4,6-trinitrenes and may be of interest as a model multi-qubit spin system for investigations of quantum computation processing. 相似文献
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Shadap Lathewdeipor Tyagi Jaya Lakshmi Poluri Krishna Mohan Novikov Sergei Lo Chun-Wan Timothy Mozharivskyj Yurij Kollipara Mohan Rao 《Transition Metal Chemistry》2021,46(3):231-240
Transition Metal Chemistry - Metal complexes 1–9 have been synthesized by reacting the benzothiazole–pyrazole derivative ligands (L1, L2 and L3) with the metal precursors of ruthenium... 相似文献
9.
A variety of different low-coordinate iron selenide complexes is reported. These are obtained by reaction of the linear iron(I) silylamide K{18c6}[Fe(N(Dipp)SiMe3)2] (Dipp=2,6-diisopropylphenyl) with red selenium. Careful adjustment of the reaction conditions results in the formation of unique low-coordinate selenido iron complexes, namely a monoselenide bridged [2Fe−1Se]2+ complex, as well as mononuclear iron per- and triselenides. Further, C−H bond activation of one of the silylamide ligands by a putative terminal iron monoselenide is observed. 相似文献
10.
Nedjla Zehani Rochdi Kherrat Sergei V. Dzyadevych 《International journal of environmental analytical chemistry》2015,95(5):466-479
Organophosphate pesticides (OPs) have been intensively used as insecticides in agriculture; after entering the aquatic environment, they may affect a wide range of organisms. A conductometric enzymatic biosensor based on lipase extracted from Candida rugosa (CRL) has therefore been developed for the direct and rapid quantitative detection of organophosphate pesticides: diazinon, methyl parathion and methyl paraoxon in water. The biosensor signal and response time were obtained under optimum conditions, the enzyme being immobilised in the presence of gold nanoparticles. Under these conditions, the enzymatic biosensor was able to measure concentrations as low as 60 µg/L of diazinon, 26 µg/L of methyl parathion and 25 µg/L of methyl paraoxon very rapidly (response time: 3 min). Moreover, this CRL biosensor was not sensitive to interferences such as carbamates. It presented good storage stability for 21 days when kept at 4°C and it was successfully applied to real samples. 相似文献