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961.
962.
963.
Natalia Domracheva Anisoara Mirea Markus Schwoerer Laura Torre-Lorente Günter Lattermann 《Chemphyschem》2006,7(12):2567-2577
Copper(II) complexes formed by coordination of the Cu(II) ion with liquid-crystalline poly(propylene imine) dendrimer ligand (L) of the first (complex 1) and second (complex 2) generations with various Cu(II) contents (x = Cu/L) have been studied by electron paramagnetic resonance (EPR) spectroscopy. The existence of a redox-active blue complex 1 (x = 1.9) and the copper(II) nitrate electron transfer associated with the valence tautomerism are revealed for the first time in copper-based dendrimers. It has been shown that the electronic structure of the blue complex 1 (x = 1.9) is adequately described as a mixed-valence dimer containing d9- and diamagnetic d10-configurated copper ions, and an antiferromagnetically coupled NO3* radical arising on the nitrate-bridged counter ligand. The activation energy value found for the electron transfer is about 0.35 meV, which indicates a low-energy charge dynamic. The ability of the blue and green complexes 1 (x = 1.9) dissolved in isotropic solvents to orient themselves in the magnetic field was revealed by EPR spectroscopy. The degree of orientation of the molecular z axis (S(z)) of these complexes in the magnetic field differs, depending on the type of copper(II)-complexing site in the dendrimer ligand, and can reach 0.76, which is close to S(z) = 1 (completely aligned system). A combination of magnetic and orientational parameters indicates an NO4 environment of the Cu(II) ion in green complex 1 (x = 1.9), and confirms the chain structure with intermolecular Cu(II)-NO3-Cu(II) bridges between Cu(II) centres in columns. 相似文献
964.
Kelly A. Daniel Laura A. Kopff Eric V. Patterson 《Journal of Physical Organic Chemistry》2008,21(4):321-328
The reaction of the chemical warfare agent VX with hydroxide and hydroperoxide has been studied using a combination of correlated molecular orbital and density functional theory. It is found that the alkaline hydrolysis leads to a mixture of neurotoxic and non‐toxic products while hydroperoxidolysis leads to exclusive formation of non‐toxic products. Natural bond orbital (NBO) analysis is used to rationalize the observation that hydroxide will attack opposite the alkoxide ligand, while hydroperoxide will attack opposite the thiolate. The current results are in good agreement with previous experimental and computational work and serve to clarify the mechanism for destruction of this highly potent nerve agent. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
965.
Flavio Pressacco Marcellino Gaudenzi Antonino Zanette Laura Ziani 《European Journal of Operational Research》2008
With reference to the evaluation of the speed–precision efficiency of pricing and hedging of American Put options, we present and discuss numerical results obtained on the basis of four different large enough random samples according to the relevance of the American quality (relative importance of the early exercise opportunity) of the options. Here we provide a comparison of the best methods (lattice based numerical methods and an approximation of the American Premium analytical procedure) known in literature along with some key methodological remarks. 相似文献
966.
Damiana Scuteri Laura Rombol Takafumi Hayashi Chizuko Watanabe Shinobu Sakurada Kengo Hamamura Tsukasa Sakurada Paolo Tonin Giacinto Bagetta Luigi A. Morrone Maria Tiziana Corasaniti 《Molecules (Basel, Switzerland)》2022,27(15)
Chronic pain is one of the most common causes of the need for clinical evaluation, acquiring more importance in the elderly with cognitive impairment. Reduced self-reporting capabilities cause unrelieved pain contributing to the development of agitation. Safe and effective pain treatment can afford the management of agitation without the serious increase in death risk associated with neuroleptics. To this aim, the essential oil of bergamot (BEO), proven by rigorous evidence to have strong preclinical anti-nociceptive and anti-allodynic properties, has been engineered (NanoBEO, patent EP 4003294) to allow randomized, double-blind, placebo-controlled trials (BRAINAID, ). The present study: (1) assesses the analgesic effects of a single therapeutic dose of NanoBEO, as supplied by an airless dispenser for clinical translation, in models of inflammatory, neuropathic, and sensitization types of pain relevant to clinic; (2) provides a dose–response analysis of the efficacy of NanoBEO on scratching behavior, a typical behavioral disturbance occurring in dementia. A single therapeutic dose of NanoBEO confirms efficacy following thirty minutes pre-treatment with capsaicin and on the central sensitization phase induced by formalin. Moreover, it has an ID50 of 0.6312 mg and it is efficacious on static and dynamic mechanical allodynia. Altogether, the gathered results strengthen the potential of NanoBEO for clinical management of pain and agitation. NCT04321889相似文献
967.
Vittorio Crescenzi Andrea Francescangeli Anna Laura Segre Donatella Capitani Luisa Mannina Davide Renier Davide Bellini 《Macromolecular bioscience》2002,2(6):272-279
Hydrogels have been prepared using two partially deacetylated hyaluronan (deHA) samples having a molar ratio of free amino groups to total initial N-acetamido groups equal to 23 and 33%, respectively. Taking advantage of such primary amino functionalities, polymeric networks could be easily obtained in aqueous media by means of two different crosslinking procedures, namely: a) Ugi multicomponent reactions and, more simply, b) glutaraldehyde reticulation. In this paper, we wish to report on the synthesis of deHA based hydrogels and, in particular, on their structural elucidation as obtained by NMR studies.
968.
With the growing interest in more environmentally friendly solvents and processes, the introduction of Natural Deep Eutectic Solvents (NaDES) as low cost, non-toxic and biodegradable solvents represent a new opportunity for green and sustainable chemistry. Thanks to their remarkable advantages, NaDES are now arousing growing interest in many fields of research such as food, health, cosmetics and biofuels. Around the world, NaDES are seen as a promising alternative to commonly used petrochemical solvents. The objective of this review is to draw up a panorama of the existing skills on NaDES in French laboratories and industries for the valuation of natural products. This review therefore focuses on current applications, skills and perspectives, in order to analyze the place of French research in the use of NaDES for the valorization of biomass since 2015. 相似文献
969.
Carmela Maria Montone Sara Elsa Aita Anna Arnoldi Anna Laura Capriotti Chiara Cavaliere Andrea Cerrato Carmen Lammi Susy Piovesana Giulia Ranaldi Aldo Lagan 《Molecules (Basel, Switzerland)》2021,26(21)
This work describes an untargeted analytical approach for the screening, identification, and characterization of the trans-epithelial transport of green tea (Camellia sinensis) catechin extracts with in vitro inhibitory effect against the SARS-CoV-2 papain-like protease (PLpro) activity. After specific catechin extraction, a chromatographic separation obtained six fractions were carried out. The fractions were assessed in vitro against the PLpro target. Fraction 5 showed the highest inhibitory activity against the SARS-CoV-2 PLpro (IC50 of 0.125 μg mL−1). The untargeted characterization revealed that (−)-epicatechin-3-gallate (ECG) was the most abundant compound in the fraction and the primary molecule absorbed by differentiated Caco-2 cells. Results indicated that fraction 5 was approximately 10 times more active than ECG (IC50 value equal to 11.62 ± 0.47 μg mL−1) to inhibit the PLpro target. Overall, our findings highlight the synergistic effects of the various components of the crude extract compared to isolated ECG. 相似文献
970.
Fabin Fernndez-Luqueo Gabriela Medina-Prez Elizabeth Prez-Soto Salvador Espino-Manzano Laura Peralta-Adauto Sergio Prez-Ríos Rafael Campos-Montiel 《Molecules (Basel, Switzerland)》2021,26(21)
The acid fruit of the "xoconostle" cactus belongs to the genus Opuntia family of cacti. It is used as a functional food for its bioactive compounds. Several studies reported that xoconostle fruits have a high amount of ascorbic acid, betalains, phenols, tannins, and flavonoids. These compounds confer antioxidant, antibacterial, anti-inflammatory, and hepatoprotective gastroprotective activity. Xoconostle fruit extracts were tested by in vitro assays where the digestion conditions were simulated to measure their stability. At the same time, the extracts were protected by encapsulation (microencapsulation, multiple emulsions, and nanoemulsions). Applications of encapsulated extracts were probed in various food matrices (edible films, meat products, dairy, and fruit coatings). The xoconostle is a natural source of nutraceutical compounds, and the use of this fruit in the new food could help improve consumers’ health. 相似文献