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381.
Vanessa A. dos Santos Lidia S. Shul''pina Dario Veghini Dalmo Mandelli Georgiy B. Shul''pin 《Reaction Kinetics and Catalysis Letters》2006,88(2):339-348
Summary The dinuclear manganese(IV) complex [LMn(O)3MnL](PF6)2 (1, L = 1,4,7-trimethyl-1,4,7-triazacyclononane) catalyzes the extremely efficient oxidation of alcohols with hydrogen peroxide
at room temperature. Oxalic acid is an obligatory co-catalyst. The oxidation of isopropanol, for example, yields acetone with
turnover numbers up to 40000 after 5-10 h in the absence of a solvent. 2-Cyanoethanol was oxidized by this system with somewhat
lower efficiency (conversion 70%). The catalytically active cation from salt 1 was obtained in an insoluble form containing
a heteropoly anion [Mn2O3(TMTACN)2]2[SiW12O40]. Oxidation of 2-cyanoethanol using this heterogenized catalyst and oxalic acid gave the oxo-products with the 54% total
yield. 相似文献
382.
Lidia A. Zaozerskaya 《Journal of Mathematical Modelling and Algorithms》2006,5(2):201-213
We study a supply management problem with a linear cost function and its mixed integer program. A parametric family of such problems, possessing exponential L
k
-coverings, is constructed. Besides, the NP-hard expansion of the family, which has the same property, is formulated. 相似文献
383.
Dr. Alexey N. Bilyachenko Dr. Mikhail M. Levitsky Alexey I. Yalymov Prof. Alexander A. Korlyukov Prof. Viktor N. Khrustalev Dr. Anna V. Vologzhanina Lidia S. Shul'pina Dr. Nikolay S. Ikonnikov Dr. Alexander E. Trigub Pavel V. Dorovatovskii Dr. Xavier Bantreil Dr. Frédéric Lamaty Dr. Jérôme Long Prof. Joulia Larionova Dr. Igor E. Golub Prof. Elena S. Shubina Prof. Georgiy B. Shul'pin 《Angewandte Chemie (International ed. in English)》2016,55(49):15360-15363
A series of four unprecedented heterometallic metallagermsesquioxanes were synthesized. Their cage‐like architectures have a unique type of molecular topology consisting of the hexairon oxo {Fe6O19} core surrounded in a triangular manner by three cyclic germoxanolates [PhGe(O)O]5. This structural organization induces antiferromagnetic interactions between the FeIII ions through the oxygen atoms. Evaluated for this first time in catalysis, these compounds showed a high catalytic activity in the oxidation of alkanes and the oxidative formation of benzamides from alcohols. 相似文献
384.
Frontispiece: Cage‐like Copper(II) Silsesquioxanes: Transmetalation Reactions and Structural,Quantum Chemical,and Catalytic Studies 下载免费PDF全文
Dr. Alexey N. Bilyachenko Dr. Marina S. Dronova Alexey I. Yalymov Dr. Frédéric Lamaty Dr. Xavier Bantreil Prof. Jean Martinez Christelle Bizet Lidia S. Shul'pina Prof. Alexander A. Korlyukov Dmitry E. Arkhipov Dr. Mikhail M. Levitsky Prof. Elena S. Shubina Dr. Alexander M. Kirillov Prof. Georgiy B. Shul'pin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24)
385.
Anna Przybylska-Balcerek Tomasz Szablewski Lidia Szwajkowska-Michaek Dariusz
wierk Renata Cegielska-Radziejewska Zbigniew Krejpcio Elbieta Suchowilska ukasz Tomczyk Kinga Stuper-Szablewska 《Molecules (Basel, Switzerland)》2021,26(10)
Due to the health-promoting properties of elderberry fruits, which result from their rich chemical composition, this raw material is widely used in herbal medicine and the food industry. The aim of the study was to demonstrate the antibacterial activity of the elderberry fruit extracts. The research showed that the content of phenolic acids and flavonoids in the extracts determined their antibacterial activity. The research showed that the content of phenolic acids and flavonoids in the extracts determined their antibacterial activity. The following phenolic acids were predominant: chlorogenic acid, sinapic acid, and t-cinnamic acid. Their average content was, respectively, 139.09, 72.84, 51.29 mg/g extract. Rutin and quercetin (their average content was 1105.39 and 306.6 mg/g extract, respectively) were the dominant flavonoids. The research showed that the elderberry polyphenol extracts exhibited activity against selected strains of bacteria within the concentration range of 0.5–0.05%. The following bacteria were the most sensitive to the extracts: Micrococcus luteus, Proteus mirabilis, Pseudomonas fragii, and Escherichia coli. Of the compounds under analysis, apigenin, kaempferol and ferulic, protocatechuic, and p-coumarin acids had the greatest influence on the high antibacterial activity of elderberry extracts. The results of the microbiological and chemical analyses of the composition of the extracts were analyzed statistically to indicate the bioactive compounds of the greatest antimicrobial significance. 相似文献
386.
387.
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389.
Lidia Leporini Luigi Menghini Marzia Foddai Giacomo Luigi Petretto Mario Chessa Bruno Tirillini 《Natural product research》2015,29(10):899-907
Ethanol extracts of Stachys glutinosa L. (Lamiaceae) were investigated for antioxidative properties, as well as antiproliferative action on various cell lines. The antioxidant activities were investigated by ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulphonic acid) assay, DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging, β-carotene/linoleic acid assay, scavenging of hydrogen peroxide (horseradish peroxidase test), superoxide anion scavenging, and hypochlorous acid scavenging (taurine test). The antioxidant activity was reported as IC50 and reveals antioxidant effects. Antiproliferative effects were measured in vitro on three cell lines: HepG2 (human hepatocarcinoma), MCF7 (breast human adenocarcinoma) and C2C12 (mouse myoblast) cell lines by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The ethanol extract induced variations in cell viability on all cell lines tested. At 200 μg/mL, the effects on cell viability were ? 23%, ? 27% and ? 37%, respectively, for C2C12, MCF7 and HepG2. 相似文献
390.