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131.
Tuya Narangerel Radosaw Bonikowski Konrad Jastrzbek Alina Kunicka-Styczyska Aleksandra Pluciska Krzysztof
migielski Iwona Majak Adrian Bartos Joanna Leszczyska 《Molecules (Basel, Switzerland)》2021,26(24)
Oxytropis pseudoglandulosa is used in Mongolian traditional medicine due to its numerous reported health-promoting effects. To date, there are very few scientific reports that describe this species. In this article, its volatile oil composition, lipid extract composition, total phenolic and flavonoid content, antibacterial and allergenic properties are elucidated for the first time. Hexadecanoic acid, fokienol and tricosane were determined as the most notable components of the volatile oil, at 13.13, 11.46 and 5.55%, respectively. Methyl benzoate was shown to be the most abundant component of lipid extract at 40.69, followed by (E)-prop-2-enoic acid, 3-phenyl- and benzenepropanoic acid, at 18.55 and 9.97%. With a TPC of 6.620 mg GAE g−1 and TFC of 10.316 mg QE g−1, the plant extract of O. pseudoglandulosa indicated good antioxidant activity measured by IC50 at 18.761 µg mL−1. Of the 12 tested microorganisms, B. subtilis and S. cerevisiae were the shown to be most susceptible to the plant extract, with MIC at 2.081 and 0.260% (v/v), respectively. Bet v 1—a major birch pollen allergen found in plant-based foods—was determined to be at 192.02 ng g−1 with ELISA. Such a wide spectrum of biological activity indicated by O. pseudoglandulosa lends credence for its application in food industry. Its exerted antioxidant and antimicrobial effects could improve preservation of low-processed food dedicated for consumers afflicted with allergies. Hexadecanoic acid supplemented in foods with dietary plant extracts could add to the potential anti-inflammatory impact. The analysis of lipid makeup suggests O. pseudoglandulosa extract could also be considered as natural pesticide in organic farming. 相似文献
132.
New dichloride platinum(II) complexes with 5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one (HmtpO) have been synthesized and characterized by thermal analysis, infrared and 1H, 13C, 15N, 195Pt NMR spectroscopy. X-ray crystal structures of cis-PtCl2(NH3)(HmtpO) (1) and cis-PtCl2(HmtpO)2 · 4H2O (2b) were determined to R = 0.0332 and R = 0.0802, respectively. In both complexes the Pt(II) ions have a square-planar geometry with two adjacent corners being occupied by two nitrogens of HmtpO molecules for 2b or NH3 and HmtpO molecules for 1, whereas the remaining adjacent corners are occupied by two chloride anions. Spectroscopic data confirm the square planar geometry with N(3) bonded HmtpO, S-bonded dimethylsulfoxide and two trans chloride anions for trans-PtCl2(dmso) · 4H2O (3). 相似文献
133.
The kinetics of the reaction between N‐(2‐hydroxyalkyl) hydroparabanates (HAHP) and N,N′‐bis(2‐hydroxyalkyl) parabanates (HAP) with ethylene and propylene oxides were studied. The addition of oxiranes to imide function of HAHP led to the formation of HAP. Further reaction of HAP with oxiranes resulted in trioxoimidazolidine ring opening and polymeric products. The kinetics of the system was studied in detail. Based on the final kinetic equations, the mechanism of the reactions was postulated. The temperature dependences of kinetic parameters and analytical data provided experimental evidences supporting the mechanism. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 399–406, 2006 相似文献
134.
Iwona E. Głowacka 《Tetrahedron: Asymmetry》2009,20(19):2270-2278
The synthesis and ee determination of diethyl 3-azido-2-hydroxypropylphosphonates from 2,3-epoxypropylphosphonates have been optimised. Enantiomerically enriched diethyl (R)- and (S)-2-hydroxy-3-(1,2,3-triazol-1-yl)propylphosphonates (R)-3a–j and (S)-3a–h as well as (S)-3j were synthesised from diethyl (R)- and (S)-2,3-epoxypropylphosphonates in a reaction sequence including azidolysis followed by 1,3-dipolar cycloaddition with selected alkynes. 相似文献
135.
136.
137.
[Reaction: see text]. Two enantiocomplementary bakers' yeast enzymes reduced an alpha-chloro-beta-keto ester to yield precursors for both enantiomers of the N-benzoyl phenylisoserine Taxol side chain. After base-mediated ring closure of the chlorohydrin enantiomers, the epoxides were converted directly to the oxazoline form of the target molecules using a Ritter reaction with benzonitrile. These were hydrolyzed to the ethyl ester form of the Taxol side chain enantiomers under acidic conditions. This brief and atom-efficient route to both target enantiomers demonstrates both the synthetic utility of individual yeast reductases and the power of genomic strategies in making these catalysts available. 相似文献
138.
139.
For the first time a very weak N-N stretching band (ν5) of hydrazine was unambiguously assigned in the Fourier-transform infrared spectrum. Almost 1500 transitions with a resolution of for K′ from 0 to 6 and for all symmetry species have been analyzed. Despite some perturbations a global fit has been carried out successfully and the band center was determined at , much higher than previously expected. 相似文献
140.
The experiments involves three types of industrial wastes produced by iron works, which create serious hazards to the natural environment: (1) paint-shop sludge, (2) oil-polluted diatomite, and (3) oil-polluted scale. The choice of an appropriate and safe storage method should be based on extensive physicochemical examination.DTA, in combination with other data, allows characterization of the combustible properties of wastes. Thermoanalytical measurements were carried out in a dynamic air atmosphere. Enthalpy values were calculated from peak areas of DTA curves. Thermoanalytical data were compared with calorimetric results obtained with an oxygen bomb.
Zusammenfassung Drei Arten industrieller Abtälle eines Stahlwerks, die schwere Umweltbelastungen darstellen, wurden untersucht: (1) Lackiererei-Schlamm, (2) ölhaltiger Diatomit, (3) ölhaltiger Kesselstein. Geeignete sichere Deponien setzen ausführliche physikalisch-chemische Untersuchungen voraus. DTA in Kombination mit anderen Untersuchungen erlaubt die Charakterisierung der Verbrennungseigenschaften der Abfälle. Die thermoanalytischen Untersuchungen erfolgten im Luftstrom, die Verbrennungswärmen wurden aus den DTA-peak-Flächen berechnet. Die Ergebnisse werden mit denen kalorimetrischer Messungen in einer Sauerstoffbombe verglichen.
- , . , . , - . . . . , .相似文献