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371.
Silvana Guilardi Ruggiero Maria Teresa do Prado Gambardella Marcelo Cardoso Branco Antonio Jacinto Demuner Luis Claudio A. Barbosa Dorila Pil‐Veloso 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):868-869
The crystal structure of 21α‐fluoro‐7‐norvouacapane‐17β,21α‐lactone, C20H25FO3, a new synthetic derivative of the diterpenoid 6α,7β‐dihydroxyvouacapan‐17β‐oic acid isolated from Pterodon polygalaeflorus Benth fruits, is described. 相似文献
372.
Antonella Aresta Stefania De Santis Alessia Carocci Alexia Barbarossa Andrea Ragusa Nicoletta De Vietro Maria Lisa Clodoveo Filomena Corbo Carlo Zambonin 《Molecules (Basel, Switzerland)》2021,26(18)
Lipids from milk are important nutritional components, although their health effects, especially for animal milks, are still questioned. Four types of commercial milks, two semi-skimmed animal milks (bovine and goat) and two vegetable ones (soy and rice), along with their total and free lipid fractions recovered by sequential centrifugation or by ethyl acetate extraction, respectively, have been analyzed. A higher antioxidant ability, reported as Trolox equivalent antioxidant capacity, was found for all raw milks compared to that of rice. This trend was confirmed, except for soy milk, as ROS reduction in Caco-2 cells. The free lipid fraction was shown to have the highest antioxidant potential in both chemical and biological tests. Moreover, goat and soy raw milks positively regulated Caco-2 cell viability after an inflammatory stimulus. This effect was lost when their total lipid fraction was tested. Finally, only the free lipid fraction from rice milk preserved the Caco-2 viability after LPS stimulation. Our data demonstrated that the lipid profile of each milk, characterized by GC-MS analysis, could contribute to dictate its biological effects, and, although additional in vitro and in vivo studies are needed, they could support the literature re-evaluating the health effects of animal-based versus plant-based milks in the intestinal cellular model. 相似文献
373.
de Sousa GF Deflon VM Gambardella MT Francisco RH Ardisson JD Niquet E 《Inorganic chemistry》2006,45(11):4518-4525
The synthesis and the IR, NMR (1H, 13C, and 119Sn), and M?ssbauer spectroscopies and single-crystal X-ray diffraction studies of seven-coordinated diorganotin(IV) complexes, namely, [Ph2Sn(Hdapsc)]Cl.H2O.DMF [7; H(2)dapsc = 2,6-diacetylpyridine bis(semicarbazone)], [Me(2)Sn(H2,6Achexim)]Br.H2O [8; H(2)2,6Achexim = 2,6-diacetylpyridine bis(3-hexamethyleneiminylthiosemicarbazone)], [Me(2)Sn(dapmts)] [9; H(2)dapmts = 2,6-diacetylpyridine bis(4-methythiosemicarbazone)], and [nBu2Sn(dapmdtc)] [10; H(2)dapmdtc = 2,6-diacetylpyridine bis(S-methydithiocarbazate)], were done. The determination of the structures of [Ph(2)Sn(Hdapsc)]+, [Me2Sn(H2,6Achexim)]+ and [Me2Sn(dapmts)], [nBu2Sn(dapmdtc)] revealed the presence of monocationic and neutral complexes, respectively. The structures consist of monomeric units in which the Sn(IV) ions exhibit distorted pentagonal-bipyramidal geometries, with the X,N,N,N,X-donor (X = O, S) systems of the ligands lying in the equatorial plane and the organic groups in the apical positions. The C-Sn-C angle in the seven-coordinated diorganotin(IV) complexes was estimated using a correlation between M?ssbauer and X-ray data based on the point-charge model and using new values obtained in this work for [alkyl] = -1.00 mm s(-1) and [aryl] = -0.80 mm s(-1) for complexes containing O,N,N,N,O-pentadentate ligands and new values for [alkyl] = -0.87 mm s(-1) and [aryl] = -0.75 mm s(-1) for complexes containing S,N,N,N,S-pentadentate ligands. 相似文献
374.
Alessia?MarigoEmail author Benedetto?Piccoli 《NoDEA : Nonlinear Differential Equations and Applications》2004,11(1):73-94
In this paper we consider systems with cooperative
controls. Such a model turns out to be efficient in those cases where
one has to deal with different goals, as optimality and safety issues,
at the same time. On the other hand, the drawback of this approach is
the presence of discontinuities of the various controls. To deal with
this problem, we give a general strategy, which is based on the
concept of Krasowskii solution to discontinuous ODEs.
Such a strategy is then applied to the safety driving of the
Dubins car. 相似文献
375.
376.
We present a compact experimental realization of the interaction among five field modes in a chi(2) nonlinear crystal. The classical evolution of the fields can be analytically described assuming that two of the fields play the role of nondepleted pumps. If one of the fields has a nonzero input amplitude, then the other two fields at the output are holographic replicas of the input signal. 相似文献
377.
Iridoids from seeds of Gentiana lutea 总被引:1,自引:0,他引:1
In the seeds of Gentiana lutea L. there were also detected, in addition to the known sweroside and getiopicroside, loganic acid 3 and trifloroside 4 that is present as main glycosidic component. The structures of 3 and 4 were established by spectroscopic studies. 相似文献
378.
379.
Simone Manetto Giulia Mazzoccanti Alessia Ciogli Claudio Villani Francesco Gasparrini 《Journal of separation science》2020,43(9-10):1653-1662
The use of the tetrabutylammonium additive was investigated in the ultra‐high performance reversed‐phase liquid chromatographic elution of basic molecules of pharmaceutical interest. When added to the mobile phase at low pH, the hydrophobic tetrabutylammonium cation interacts with the octadecyl chains and with the residual silanols, thus imparting a positive charge to the stationary phase, modulating retention and improving peak shape of protonated basic solutes. Two sources of additive were tested: a mixture of tetrabutylammonium hydroxide/trifluoroacetic acid and tetrabutylammonium hydrogen sulfate. Retention and peak shape of 11 basic pharmaceutical compounds were evaluated on commercially available ultra‐fast columns packed with octadecyl stationary phases (Ascentis Express C18 2.0 µm, Acquity BEH C18 1.7 µm, Titan C18 1.9 µm). All columns benefit from the use of additive, especially tetrabutylammonium hydrogen sulfate, providing very symmetric peaks with reasonable retention times. Focusing on the probe compounds amitriptyline and sertraline, efficiency and asymmetry values were investigated at increasing retention factor. The trend is very different to that obtained in reversed‐phase conditions and the effect lies in the complex molecular interaction mechanisms based on hydrophobic and ion exchange interactions as well as electrostatic repulsion. 相似文献
380.