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301.
Agata Hogendorf Adam S. Hogendorf Rafa Kurczab Grzegorz Sataa Bernadeta Szewczyk Paulina Cielik Gniewomir Latacz Jadwiga Handzlik Tomasz Lenda Katarzyna Kaczorowska Jakub Staro Ryszard Bugno Beata Duszyska Andrzej J. Bojarski 《Molecules (Basel, Switzerland)》2021,26(15)
A series of N-skatyltryptamines was synthesized and their affinities for serotonin and dopamine receptors were determined. Compounds exhibited activity toward 5-HT1A, 5-HT2A, 5-HT6, and D2 receptors. Substitution patterns resulting in affinity/activity switches were identified and studied using homology modeling. Chosen hits were screened to determine their metabolism, permeability, hepatotoxicity, and CYP inhibition. Several D2 receptor antagonists with additional 5-HT6R antagonist and agonist properties were identified. The former combination resembled known antipsychotic agents, while the latter was particularly interesting due to the fact that it has not been studied before. Selective 5-HT6R antagonists have been shown previously to produce procognitive and promnesic effects in several rodent models. Administration of 5-HT6R agonists was more ambiguous—in naive animals, it did not alter memory or produce slight amnesic effects, while in rodent models of memory impairment, they ameliorated the condition just like antagonists. Using the identified hit compounds 15 and 18, we tried to sort out the difference between ligands exhibiting the D2R antagonist function combined with 5-HT6R agonism, and mixed D2/5-HT6R antagonists in murine models of psychosis. 相似文献
302.
In the present paper we consider the Bézier variant of BBH-Kantorovich operators Jn,αf for functions f measurable and locally bounded on the interval [0, ∞) with α ? 1. By using the Chanturiya modulus of variation we estimate the rate of pointwise convergence of Jn,αf(x) at those x > 0 at which the one-sided limits f(x+), f(x−) exist. The very recent result of Chen and Zeng (2009) [L. Chen, X.M. Zeng, Rate of convergence of a new type Kantorovich variant of Bleimann-Butzer-Hahn Operators, J. Inequal. Appl. 2009 (2009) 10. Article ID 852897] is extended to more general classes of functions. 相似文献
303.
We define the degree of nonclassicality of a one-mode Gaussian state of the quantum electromagnetic field in terms of the Bures distance between the state and the set of all classical one-mode Gaussian states. We find the closest classical Gaussian state and the degree of nonclassicality using a recently established expression for the Uhlmann fidelity of two single-mode Gaussian states. The decrease of nonclassicality under thermal mapping is carefully analyzed. Along the same lines, we finally present the evolution of nonclassicality during linear amplification. 相似文献
304.
Aiste Balciunaitiene Viktorija Puzeryte Vitalijs Radenkovs Inta Krasnova Patrick B. Memvanga Pranas Viskelis Paulina Streimikyte Jonas Viskelis 《Molecules (Basel, Switzerland)》2022,27(22)
Silver nanoparticles (AgNPs) biosynthesized using aqueous medical plant extracts as reducing and capping agents show multiple applicability for bacterial problems. The aim of this study was to expand the boundaries on AgNPs using a novel, low-toxicity, and cost-effective alternative and green approach to the biosynthesis of metallic NPs using Calendula officinalis (Calendula) and Hyssopus officinalis (Hyssopus) aqueous extracts. The formation of AgNPs was confirmed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) techniques. The effectiveness of biosynthesized AgNPs in quenching free radicals and inhibiting the growth of Gram-positive and Gram-negative microorganisms was supported by in vitro antioxidant activity assay methods and using the Kirby–Bauer disk diffusion susceptibility test, respectively. The elucidated antimicrobial and antioxidative activities of medical plant extracts were compared with data from the engineered biosynthetic AgNPs. The antimicrobial effect of engineered AgNPs against selected test cultures was found to be substantially stronger than for plant extracts used for their synthesis. The analysis of AgNPs by TEM revealed the presence of spherical-shaped nano-objects. The size distribution of AgNPs was found to be plant-type-dependent. The smaller AgNPs were obtained with Hyssopus extract (with a size range of 16.8 ± 5.8 nm compared to 35.7 ± 4.8 nm from Calendula AgNPs). The AgNPs’ presumably inherited biological functions of Hyssopus and Calendula medical plants can provide a platform to combat pathogenic bacteria in the era of multi-drug resistance. 相似文献
305.
306.
Justina Gaidukevi? Jurgis Barkauskas Anna Malaika Paulina Rechnia-Gor?cy Aleksandra Mo?d?yńska Vitalija Jasulaitien? Mieczys?aw Koz?owski 《催化学报》2018,39(10):1633-1645
本文研究了不同石墨烯基材料用作转酯化反应制备生物柴油催化剂的性能.将磺酸基或磷酸盐基嫁接到热还原的氧化石墨烯表面,制备了固体酸石墨烯基样品.并采用扫描电镜、X射线衍射、热重分析、X射线光电子能谱、N_2吸附-脱附法、电位滴定法、元素分析以及红外光谱法对所制样品进行了全面表征.将所制样品用于130℃带压力的条件下菜籽油与甲醇转酯化反应中,并将其催化活性与商用的多相酸催化剂Amberlyst-15的进行了比较.结果表明,所有改进的样品在转酯化反应中均表现出催化活性,但各样品上生物柴油产率差别较大.其中以苯二氮磺酸基功能化的热还原氧化石墨烯样品上脂肪酸甲酯产率最高,反应6 h后达70%,也明显高于商用催化剂Amberlyst-15.该样品也表现出良好的重复使用性能. 相似文献
307.
Hemant K. Sharma Paulina E. Gonzalez Alexander L. Craig Sanchita Chakrabarty Alejandro Metta‐Magaña Prof. Keith H. Pannell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(22):7363-7366
Compound Et3SiOCH2NMe2 transfers Me2NCH2 to R2NH (R2=Et2, PhMe, [Cr(η6‐C6H5)(CO)3]Me, PhH) to form previously unknown diaminomethanes, Me2NCH2NR2 and, in the case of R2=PhH, the triamine Me2NCH2N(Ph)CH2NMe2. The diaminomethanes exhibit an unreported disproportionation to a mixture of (R2N)2CH2, (Me2N)2CH2, and Me2NCH2NR2, which can be trapped as their [Mo(CO)4(diamine)] complexes. Whereas PhMeNCH2NMe2 is a labile material, the metal‐substituted ([(η6‐C6H5)Cr(CO)3]MeNCH2NMe2 is a stable material. The triamine Me2NCH2N(Ph)CH2NMe2 is unstable with respect to transformation to 1,3,5‐triphenyltriazine, but is readily trapped as the bidentate‐triamineMo(CO)4. All metal complexes were characterized by single‐crystal X‐ray diffraction. 相似文献
308.
The absorption and fluorescence properties of nifedipine (NPDHP), felodipine (CPDHP) and a series of structurally related 1,4-dihydropyridines were studied in aqueous solution and organic solvents of different properties. The absorption and fluorescence spectra were found to depend on the chemical nature of the substituents at the position 4 of the 1,4-dihydropyridine ring (DHP) and on solvent properties. In aqueous solution, the fluorescence spectra of 4-phenyl substituted compounds are blue-shifted with respect to the alkyl substituted compounds. The more fluorescent compound is CPDHP. Nifedipine is not fluorescent. All compounds, with the exception of CPDHP, present monoexponential fluorescence decay with very short lifetime (0.2-0.4 ns). CPDHP showed a biexponential emission decay with a long-lived component of 1.7 ns; this behavior is explained in terms of different conformers because of the hindered rotation of the phenyl group by the ortho-substitution. Analysis of the solvent effect on the maximum of the absorption spectrum by using the linear solvent-energy relation solvato-chromic equation indicates the redshifts are influenced by the polarizability, hydrogen bonding ability and the hydrogen bond acceptance of the solvent. Whereas, the fluorescence characteristics (spectra, quantum yields and lifetimes) are sensitive to the polarizabilty and hydrogen bond ability of the solvents. Photo-decomposition of nifedipine is dependent on the solvent properties. Faster decomposition rates were obtained in nonprotic solvents. The 4-carboxylic derivative goes to decarboxylation. Under similar conditions, the other DHP compounds did not show appreciable photodecomposition. 相似文献
309.
Hernández PI Moreno D Javier AA Torroba T Pérez-Tomás R Quesada R 《Chemical communications (Cambridge, England)》2012,48(10):1556-1558
The tambjamine alkaloids and related synthetic analogs are potent transmembrane anion tranporters promoting bicarbonate/chloride exchange in model phospholipid liposomes and discharging pH gradients in living cells. 相似文献
310.
Straightforward Synthetic Protocol for the Introduction of Stabilized C Nucleophiles in the BODIPY Core for Advanced Sensing and Photonic Applications 下载免费PDF全文
Brenda D. Gutiérrez‐Ramos Dr. Jorge Bañuelos Dr. Teresa Arbeloa Prof. Iñigo López Arbeloa Paulina E. González‐Navarro Prof. Kazimierz Wrobel Dr. Luis Cerdán Dr. Inmaculada García‐Moreno Prof. Angel Costela Prof. Eduardo Peña‐Cabrera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1755-1764
A straightforward synthetic protocol to directly incorporate stabilized 1,3‐dicarbonyl C nucleophiles to the meso position of BODIPY (4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene) is reported. Soft nucleophiles generated by deprotonation of 1,3‐dicarbonyl derivatives smoothly displace the 8‐methylthio group from 8‐(methylthio)BODIPY analogues in the presence of CuI thiophenecarboxylate in stoichiometric amounts at room temperature. Seven highly fluorescent new derivatives are prepared with varying yields (20–92 %) in short reaction times (5–30 min). The excellent photophysical properties of the new dyes allow focusing on applications never analyzed before for BODIPYs substituted with stabilized C nucleophiles such as pH sensors and lasers in liquid and solid state, highlighting the relevance of the synthetic protocol described in the present work. The attainment of these dyes, with strong UV absorption and highly efficient and stable laser emission in the green spectral region, concerns to one of the greatest challenges in the ongoing development of advanced photonic materials with relevant applications. In fact, organic dyes with emission in the green are the only ones that allow, by frequency‐doubling processes, the generation of tunable ultraviolet (250‐350 nm) radiation, with ultra‐short pulses. 相似文献