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31.
We consider numerical approximation to the solution of non-autonomous evolution equations. The order of convergence of the
simplest possible Magnus method is investigated. 相似文献
32.
Discrete Ti−O−Ti Complexes: Visible-Light-Activated,Homogeneous Alternative to TiO2 Photosensitisers
Kira Behm Dr. Eszter Fazekas Prof. Martin J. Paterson Dr. Filipe Vilela Dr. Ruaraidh D. McIntosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(43):9486-9494
A series of novel bimetallic TiIV amine bis(phenolate) complexes was synthesised and fully characterised. X-ray crystallography studies revealed distorted octahedral geometries around the Ti centres with single or double oxo-bridges connecting the two metals. These robust, air- and moisture-stable complexes were employed as photosensitisers generating singlet oxygen following irradiation with visible light (420 nm) LED module in a commercial flow reactor. All five complexes showed high activity in the photo-oxygenation of α-terpinene and achieved complete conversion to ascaridole in four hours at ambient temperature. The excellent selectivity of these photosensitisers towards ascaridole (vs. transformation to p-cymene) was demonstrated with control experiments using a traditional TiO2 catalyst. Further comparative studies employing the free pro-ligands as well as a monometallic analogue highlighted the importance of the ‘TiO2-like’ moiety in the polymetallic catalysts. Computational studies were used to determine the nature of the ligand to metal charge transfer (LMCT) states and singlet–triplet gaps for each complex, the calculated trends in the UV-vis absorption spectra across the series agreed well with the experimental results. 相似文献
33.
Judit Frank Piroska Rkczy Lajos Radics Eszter Gcs-Baitz 《Journal of heterocyclic chemistry》1981,18(5):985-990
Diazotisation of the 5-amino function in 6,7-alkoxy-l-ethyl-l,4-dihydro-4-oxoquinoline-3-carboxylic acids led to various products. Dediazoniation was always accompanied by fission of the 6-alkoxy substituent; 6,7-methylenedioxy groups gave formaldehyde which could form a m-dioxino ring. Hydrolysis of the diazonium chlorides resulted in halo-dediazoniation. 相似文献
34.
The thermal properties of fumaric acid and maleic acid were investigated. It was found that differences in their thermal decompositions provide a possibility for their determination. The thermoanalytical determination of their mixtures was carried out derivatographically. 相似文献
35.
Various primary amides and ketoamides have been obtained in good yields in a two-step reaction sequence. The first step involves the synthesis of aryl/alkenyl N-tert-butyl amides and aryl N-tert-butyl ketoamides from the corresponding iodides via palladium-catalysed carbonylation in the presence of t-BuNH2 as the nucleophile. Carbonylation was followed by selective cleavage of the t-Bu group using TBDMSOTf as the reagent. 相似文献
36.
Eszter?Gács-Baitz Orsolya?EgyedEmail author Aldo?Taticchi Lucio?Minuti Assunta?Marrocchi 《Structural chemistry》2005,16(6):581-585
Our ongoing study on cycloaddition reactions of dienes with different dienophiles afforded a great variety of derivatives
with interesting molecular structures and electronic behavior. A new type of angularly annelated [2.2]paracyclophane (3) has been synthesize by the Diels–Alder reaction of 4-(2-propenyl[2.2]paracyclophane (1) and 1,4-benzoquinone (2) under high pressure conditions. The structure determination of this compound has been achieved by NMR measurements and semiempirical
calculations. 相似文献
37.
HPLC analysis of in vivo intestinal absorption and oxidative metabolism of salicylic acid in the rat
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Mónika Kuzma Eszter Nyúl Mátyás Mayer Emil Fischer Pál Perjési 《Biomedical chromatography : BMC》2016,30(12):2044-2052
In vivo absorption and oxidative metabolism of salicylic acid in rat small intestine was studied by luminal perfusion experiment. Perfusion through the lumen of proximal jejunum with isotonic medium containing 250 μm sodium salicylate was carried out. Absorption of salicylate was measured by a validated HPLC‐DAD method which was evaluated for a number of validation characteristics (specificity, repeatability and intermediate precision, limit of detection, limit of quantification, linearity and accuracy). The method was linear over the concentration range 0.5–50 μg/mL. After liquid–liquid extraction of the perfusion samples oxidative biotransformation of salicylate was also investigated by HPLC‐MS. The method was linear over the concentration range 0.25–5.0 μg/mL. Two hydroxylated metabolites of salicylic acid (2,5‐dihydroxybenzoic acid and 2,3‐dihydroxybenzoic acid) were detected and identified. The mean recovery of extraction was 72.4% for 2,3‐DHB, 72.5% for 2,5‐DHB and 50.1% for salicylic acid, respectively. The methods were successfully applied to investigate jejunal absorption and oxidative metabolism of sodium salicylate in experimental animals. The methods provide analytical background for further metabolic studies of salycilates under modified physiological conditions. 相似文献
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