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排序方式: 共有133条查询结果,搜索用时 15 毫秒
1.
Daniel Fernndez Daniel Vega Javier A. Ellena Gustavo Echeverría 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m418-m420
In the title compound, potassium 2‐butyl‐4‐chloro‐1‐{[2′‐(5‐tetrazolido)biphenyl‐4‐yl]methyl}‐1H‐imidazol‐5‐ylmethanol, K+·C22H22ClN6O?, the imidazole and tetrazole rings are at angles of 85.0 (2) and 51.8 (1)°, respectively, to the phenyl rings to which they are attached, while the dihedral angle between the latter two rings is 46.7 (1)°. The coordination sphere of the metal cation consists of six tetrazoyl N atoms, the methanol O atom and the π cloud of one of the phenyl rings. These interactions determine the formation of columns of molecular anions that lie parallel to the b axis, while hydrogen bonding contributes to intercolumnar cohesion. Far from the centre of the columns, the hydrocarbon chain is immersed in a hydrophobic environment. 相似文献
2.
Marcelo O. Santiago Alzir A. Batista Marcio P. de Araújo Claudio L. Donnici Icaro de S. Moreira Eduardo E. Castellano Javier Ellena Sauli dos Santos Jr Salete L. Queiroz 《Transition Metal Chemistry》2005,30(2):170-175
A series of cis-{RuCl2(PPh3)2[4,4-(X)2-2,2-bipy]} [cis-chlorines; X=-H, -Me, -SMe, and (-Cl,-Me)] complexes have had their structures determined by single crystal X-ray diffraction. The geometry of these complexes, also determined in CH2Cl2 solution by 31P{1H}-n.m.r. spectroscopy, showed that the chemical shifts for the phosphorus atoms are slightly dependent on the pKa of the 4,4-(-X)2-2,2-bipy ligands. 相似文献
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Laís Peres Silva Ivanilson Pimenta Santos Dahara Keyse Carvalho Silva Bruna Padilha Zurita Claro dos Reis Cssio Santana Meira Marcos Venícius Batista de Souza Castro Jos Maurício dos Santos Filho Joo Honorato de Araujo-Neto Javier Alcides Ellena Rafael Gomes da Silveira Milena Botelho Pereira Soares 《Molecules (Basel, Switzerland)》2022,27(23)
Immunomodulatory agents are widely used for the treatment of immune-mediated diseases, but the range of side effects of the available drugs makes necessary the search for new immunomodulatory drugs. Here, we investigated the immunomodulatory activity of new ferrocenyl-N-acyl hydrazones derivatives (SintMed(141–156). The evaluated N-acyl hydrazones did not show cytotoxicity at the tested concentrations, presenting CC50 values greater than 50 µM. In addition, all ferrocenyl-N-acyl hydrazones modulated nitrite production in immortalized macrophages, showing inhibition values between 14.4% and 74.2%. By presenting a better activity profile, the ferrocenyl-N-acyl hydrazones SintMed149 and SintMed150 also had their cytotoxicity and anti-inflammatory effect evaluated in cultures of peritoneal macrophages. The molecules were not cytotoxic at any of the concentrations tested in peritoneal macrophages and were able to significantly reduce (p < 0.05) the production of nitrite, TNF-α, and IL-1β. Interestingly, both molecules significantly reduced the production of IL-2 and IFN-γ in cultured splenocytes activated with concanavalin A. Moreover, SintMed150 did not show signs of acute toxicity in animals treated with 50 or 100 mg/kg. Finally, we observed that ferrocenyl-N-acyl hydrazone SintMed150 at 100 mg/kg reduced the migration of neutrophils (44.6%) in an acute peritonitis model and increased animal survival by 20% in an LPS-induced endotoxic shock model. These findings suggest that such compounds have therapeutic potential to be used to treat diseases of inflammatory origin. 相似文献
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Abstract Due to the wide use of polymers in medicine, researchers are required to solve a very important problem–to understand the interaction between materials of nonphysiological origin and the surrounding biological liquids, and tissues, particularly blood. 相似文献
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Lincoln Lucilio Romualdo André Luis Bogado Eliana M.A. Valle Icaro S. Moreira Javier Ellena Eduardo E. Castellano Márcio P. de Araujo Alzir A. Batista 《Polyhedron》2008
New tetraruthenated manganese (III) porphyrins were synthesized and characterized (31P NMR, cyclic voltammetry, UV–Vis). This new system presents four units of cationic “[RuCl(dppb)(X-bipy)]+”. The electrochemical and catalytic properties of the central manganese (III) show dependence on the characteristics of the peripheral ruthenium complexes as evidenced by the Mn(III)/Mn(II) reduction potential. 相似文献
10.
Rodrigo S. Corrêa Marcelo H. dos Santos Tanus J. Nagem Javier Ellena 《Structural chemistry》2010,21(3):555-563
Oxygenated xanthones have been extensively investigated over the years, but there are few reports concerning their crystal
structure. Our chemical investigations of Brazilian plants resulted in the isolation of four natural products named 1-hydroxyxanthone
(I), 1-hydroxy-7-methoxyxanthone (II), 1,5-dihydroxy-3-methoxyxanthone (III), and 1,7-dihydroxy-3,8-dimethoxyxanthone (IV).
The structures of these compounds were established on the basis of single crystal X-ray diffraction. The xanthone nucleus
conformation is essentially planar with the substituents adopting the orientations less sterically hindered. In addition,
classical intermolecular hydrogen bonds (O–H···O) present in III and IV give rise to infinite ribbons. However, the xanthone
I does not present any intermolecular hydrogen bonds, meanwhile the xanthone II presents only a non-classical one (C–H···O).
The crystal packing of all xanthone structures is also stabilized by π–π interactions. The fingerprint plots, derived from
the Hirshfeld surfaces, exhibited significant features of each crystal structures. 相似文献