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41.
42.
F. L. Oliveira P. C. Huber W. P. Almeida J. R. Sabino R. Aparicio 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(2):119-122
The ZnII center in the dicationic complex of the title compound, [Zn(C10H7N3S)3](NO3)2·0.5C2H5OH·H2O, is in a distorted octahedral environment with imperfect noncrystallographic C3 symmetry. Each 2‐(1,3‐thiazol‐2‐yl)‐1H‐benzimidazole ligand coordinates in a bidentate manner, with the Zn—N(imidazole) bond lengths approximately 0.14 Å shorter than the Zn—N(thiazole) bond lengths. Charge‐assisted hydrogen bonds connect cations, anions and water molecules. A lattice void is occupied by an ethanol solvent molecule disordered about a crystallographic inversion center and π‐stacking is observed between one type of symmetry‐related benzene rings. 相似文献
43.
AbstractWe report here an improved, highly efficient, and general method for the ligand-free Suzuki cross-coupling reaction to the synthesis of biaryls, bipyridyls, thienylpyridine, and allylphenols. Microwave irradiation of (het)aryl halides and (hetaryl, allyl)arylboronic acid N-methyl-iminodiacetic acid (MIDA) ester, using polyurea microencapsulated palladium catalyst (Pd EnCat 30), gave the coupling adducts 1a–x in excellent yields in just 10–18 min. 相似文献
44.
Abstract The five Leslie viscosities for a mixture of two nematic materials are computed as functions of the temperature, composition and order parameter. It is shown that, for a nematic mixture of A and B, the equations describing the composition and temperature behaviour of the Leslie viscosities have the same form as those for the pure components, provided that composition-averaged values of the parameters are used. For the case where the free volume is additive, the relaxation times for the mixtures can be directly expressed as functions of the parameters for the pure components. These results are compared with the experimental data on λ1 for MBBA/EBBA mixtures, and fairly good agreement is found. 相似文献
45.
Machado Poliana A. L. Cavalcanti Marcello H. S. Silva Fábio A. B. de Almeida Eduardo T. Cardoso Marcus V. C. Mesquita Anderson F. Lemes Nelson H. T. Virtuoso Luciano S. 《Journal of solution chemistry》2022,51(3):320-344
Journal of Solution Chemistry - Liquid–liquid equilibrium (LLE) data and phase diagrams for new aqueous two-phase systems (ATPSs) containing 1-butyl-3-methylimidazolium chloride... 相似文献
46.
do Nascimento Ticiano Gomes Borges Arthur Luy Tavares Ferreira de Almeida Lara Mendes Ribeiro Êurica Adélia Nogueira Silva Fernanda Geny Calheiros da Costa Silva Valdemir do Nascimento Prata Ana Paula Basílio-Júnior Irinaldo Diniz Goulart Marília Oliveira Fonseca Morilla Demetrius Peireira de Freitas Johnnatan Duarte Aragão Cícero Flávio Soares 《Journal of Thermal Analysis and Calorimetry》2022,147(21):11949-11963
Journal of Thermal Analysis and Calorimetry - This work prepared and characterized microcapsule of Uncaria tomentosa (UT) in order to standardize a spray-dryer Uncaria tomentosa extract. The UT... 相似文献
47.
Jeferson Rodrigo Souza Pina Joo Victor Silva-Silva Josiwander Miranda Carvalho Heriberto Rodrigues Bitencourt Luciano Almeida Watanabe Juan Matheus Pereira Fernandes Guilherme Eduardo de Souza Anna Caroline Campos Aguiar Rafael Victorio Carvalho Guido Fernando Almeida-Souza Ktia da Silva Calabrese Patrícia Santana Barbosa Marinho Andrey Moacir do Rosario Marinho 《Molecules (Basel, Switzerland)》2021,26(11)
The natural compound ravenelin was isolated from the biomass extracts of Exserohilum rostratum fungus, and its antimicrobial, antiplasmodial, and trypanocidal activities were evaluated. Ravenelin was isolated by column chromatography and HPLC and identified by NMR and MS. The susceptibility of Gram-positive and Gram-negative bacteria strains to ravenelin was determined by microbroth dilution assay. Cytotoxicity was evaluated in hepatocarcinoma cells (HepG2) and BALB/c peritoneal macrophages by using MTT. SYBR Green I-based assay was used in the asexual stages of Plasmodium falciparum. Trypanocidal activity was tested against the epimastigote and intracellular amastigote forms of Trypanosoma cruzi. Ravenelin was active against Gram-positive bacteria strains, with emphasis on Bacillus subtilis (MIC value of 7.5 µM). Ravenelin’s antiparasitic activities were assessed against both the epimastigote (IC50 value of 5 ± 1 µM) and the intracellular amastigote forms of T. cruzi (IC50 value of 9 ± 2 µM), as well as against P. falciparum (IC50 value of 3.4 ± 0.4 µM). Ravenelin showed low cytotoxic effects on both HepG2 (CC50 > 50 µM) and peritoneal macrophage (CC50 = 185 ± 1 µM) cells with attractive selectivity for the parasites (SI values > 15). These findings indicate that ravenelin is a natural compound with both antibacterial and antiparasitic activities, and considerable selectivity indexes. Therefore, ravenelin is an attractive candidate for hit-to-lead development. 相似文献
48.
Moura Ramos Joaquim J. Diogo Hermínio P. 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3077-3085
Journal of Thermal Analysis and Calorimetry - The thermal behavior of the two glass-forming drugs bifonazole and lamotrigine was studied by differential scanning calorimetry (DSC); we reported a... 相似文献
49.
Sfarra Stefano Tejedor Blanca Perilli Stefano Almeida Ricardo M. S. F. Barreira Eva 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3105-3123
Journal of Thermal Analysis and Calorimetry - The water ingress phenomenon in sandwich-structured composites used in the aerospace/aeronautical sector is a current issue. This type of defect can... 相似文献
50.
The airborne transport of particles on a granular surface by the
saltation mechanism is studied through numerical simulation of
particles dragged by turbulent air flow. We calculate the
saturated flux qs and show that its dependence on the wind
strength u* is consistent with several empirical relations
obtained from experimental measurements. We propose and explain
a new relation for fluxes close to the threshold velocity ut,
namely, qs=a(u*-ut)α with α≈2. We
also obtain the distortion of the velocity profile of the wind due to the
drag of the particles and find a novel dynamical
scaling relation. We also obtain a new expression for the dependence of
the height of the saltation layer as function of the strength of the wind. 相似文献