A novel bis[2-(2-chloro-4-fluorophenyl)-1H-Benzimidazole]-hydrate was prepared from Schiff base, and its single crystalline
was obtained. The single crystalline was characterized by X-ray crystallography, and the results shows that the title complex
belongs to the triclinic system, space group (P1) with lattice parameters a = 7.592(2) ?, b = 7.595(2) ?, c = 11.886 (3) ?, V = 574(3) ?3, Mr = 352.33, Dc = 1.478 g/cm3, μ(MoKα) = 0.33 mm−1, F(000) = 262, Z = 1, the final R = 0.090 and wR = 0.209 for 2,315 observed reflections (I > 2σ(I)). The crystal structure is formed by two benzimidazole molecules which are linked by a water molecule. A UV–Vis spectrophotometer
and a fluorophotometer were used to detect the benzimizadole-hydrate crystal transformation process, which shows that benzimidazole-hydrate
can only be formed from Schiff base effectively when ortho-hydroxyl group does not exist in benzaldehyde. The synthesis mechanism
was also discussed. Compared with its Schiff base, benzimidazole-hydrate displays stronger fluorescence. 相似文献
A strategy was developed for the voltammetric determination of the antibiotic drug levofloxacin (LV) based on a glassy carbon electrode modified with a composite consisting of poly(o-aminophenol) and graphene quantum dots (PoAP/GQD) that was fabricated by electropolymerization. The PoAP/GQD composite provides a large surface area and sensing interface and strongly promotes the oxidation current of LV. Under optimal conditions, the modified GCE displays an oxidation peak current (best measured at a working voltage of 1.05 V vs. SCE) that is linearly related to the levofloxacin concentration in the range from 0.05 to 100 μM, and the detection limit is 10 nM (at an S/N of 3). The method was applied to the determination of levofloxacin in spiked milk samples where is gave recoveries between 96.0 and 101.0 %.
Graphical Abstract We describe a one-step electrochemical polymerization method to synthesize a layer of conductive film of poly(o-aminophenol) and graphene quantum dots (PoAP/GQD) onto a glassy carbon electrode (GCE) surface. The composite film exhibited high electro catalytic activity for the quantitative determination of levofloxacin by stripping voltammetry.
The present study evaluated the pathogenetic roles of three kinds of regulatory peptide. The results showed that (i) plasma endothelin(ET) level elevated significantly in septic shock rats, persistent intravenous drip of low doses ET caused development of shock state in normal rats and the irreversible outcome of light hemorrhagic shock. Furthermore, i. v. administration of specific ET-antiserum was significantly effective to septic shock rats, (Ⅱ) Plasma calcitonin gene-related peptide (CGRP) increased by 260% in septic shock rats, i. v. drip of low doses CGRP both in early and late sepsis were effective to shock rats, (Ⅱi) An-giotensin-Ⅱ (ANG-Ⅱ) contents of heart and aorta increased dramatically both in early and late septic shock, and inhibiting its increase with Captopril in late sepsis significantly improved the shock state, but results were inverse in early sepsis. It could be concluded that ET was one of the most important factors participating in the pathogenesis of shock, CGRP had a compens 相似文献
Analysis of the bisignate circular dichroism spectra of bilirubin-IXα bis-propionate salts of (S)-(-)-N, N, N-trimethyl α-phenethylammonium hydroxide reveals a preference in CHC13, (CH3)2 CO and CH3 CN solvents for folded conformations in which the propionate groups are intramolecularly H-bonded to the opposing pyrromethenone units. 相似文献