Synthesis, Characterization, Spectroscopic Properties of 2-(4-Dimethylaminophenyl)-5-fluoro-6-(morpholin-4-yl)-1H-benzimidazole and its Interaction with Calf Thymus DNA

Dimethylaminophenyl)-5-fluoro-6-(morpholin-4-yl)-1H-benzimidazole(1) has been synthesized and characterized by H-NMR, MS and elemental analysis. UV-Vis spectra of the 1 aqueous solutions at different pH values reveal that compound 1 can combine three protons. Its three protonation constants are determined by spectrophotometry and calculated by non-linear least squares. The results of steady-state fluorescence measurements indicate that a special interaction occurs between compound 1 and calf thymus DNA, of which the binding constant, Kb, is (2.30 ± 0.10)×l04 L/mol. Compound 1 in the concentration range of 10-8 to 1.2×10-6 mol/L could be used for quantitative determination of DNA.

Interaction of N-(2-Methyl Thio Phenyl)-2-Hydroxy-1-Naphthaldimine with Tin Dioxide Nanoparticles: A Spectroscopic Approach

The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.

Enhanced separation of Pd(Ⅱ)and Pt(Ⅳ)from hydrochloric acid aqueous solution using 2-((2-methoxyethyl)thio)-1H-benzimidazole

Separation of palladium(Pd)and platinum(Pt)by solvent extraction is difficult because of their extremely similar physicochemical properties.Development of new extractants with a high extraction efficiency and excellent separation selectivity is the primary focus for enhancing the separation of Pd and Pt by solvent extraction.In this study,a new extractant,2-((2-methoxyethyl)thio)-1 H-benzimidazole(MOBI),which contains N,S,and O atoms,was synthesized and used to separate Pd(Ⅱ)and Pt(Ⅳ)from a hydrochloric acid aqueous solution.The experimental results revealed that Pd(Ⅱ)and Pt(Ⅳ)were effectively separated under the optimal conditions:MOB I concentration of 0.005 mol·L^(-1),HCl concentration of0.2 mol·L^(-1),organic/aqueous(O/A)phase ratio of 1.0,and contact time of 15 min.The separation coefficient between Pd(Ⅱ)and Pt(Ⅳ)was 1246.40,which indicates that MOBI has a higher selectivity for Pd(Ⅱ)than Pt(Ⅳ).In addition,the mechanism of coordination between Pd(Ⅱ)and MOBI was demonstrated through the slope method,Fourier transform infrared spectroscopy(FTIR),hydrogen-1 nuclear magnetic resonance spectroscopy(^(1)H NMR),and carbon-13 nuclear magnetic resonance spectroscopy(^(13)C NMR).The results revealed that MOBI could coordinate with Pd(Ⅱ)via the N atom in the benzimidazole ring of MOBI molecules to form[Pd(MOBI)_(2)Cl_(2)](O).

A New Sesquiterpene-substituted Benzoic Acid from the Brown Alga Dictyopteris divaricata

A new sesquiterpene-substituted benzoic acid has been isolated from the brown Alga Dictyopteris divaricata Okam.. Its structure was elucidated as 3-[(2-hydroxy-2,5,5,8a-tetra- methyldecahydro-1-naphthalenyl)methyl]-4-hydroxybenzoic acid, named dictyvaric acid on the basis of spectroscopic methods including IR, HRFABMS, 1D and 2D NMR techniques.

Screening of chemokine receptor CCR4 antagonists by capillary zone electrophoresis

CC chemokine receptor 4(CCR4)is a kind of G-protein-coupled receptor,which plays a pivotal role in allergic inflammation.The interaction between 2-(2-(4-chloro-phenyl)-5-{[(naphthalen-1-ylmethyl)-carbamlyl]-methyl-4-oxo-thiazolidin-3-yl)-N-(3-morpholin-4-yl-propyi)-acetamide(S009)and the N-terminal extracellular tail(ML40)of CCR4 has been validated to be high affinity by capillary zone electrophoresis(CZE).The S009 is a known CCR4 antagonist.Now,a series of new thiourea derivatives have been synthesized.Compared with positive control S009,they were screened using ML40 as target by CZE to find some new drugs for allergic inflammation diseases.The synthesized compounds XJH-5,XJH-4,XJH-17 and XJH-1 displayed the interaction with ML40,but XJH-9,XJH-10,XJH-I 1,XJH-12,XJH-13,XJH-14,XJH-3,XJH-8,XJH-6,XJH-7,XJH-15,XJH-16 and XJH-2 did not bind to ML40.Both qualification and quantification characterizations of the binding were determined.The affinity of the four compounds was valued by the binding constant,which was similar with the results of chemotactic experiments.The established CEZ method is capable of sensitive and fast screening for a series of lactam analogs in the drug discovery for allergic inflammation diseases.