نتایج جستجو برای: imidazoles multicomponent nmr
تعداد نتایج: 72088 فیلتر نتایج به سال:
Modelling the mixing process of multicomponent liquids is still an open problem. In this work the possibility to use nuclear magnetic resonance (NMR) to measure concentration profiles during interdiffusion of a binary system is discussed. NMR is a non-invasive technique that can be used to measure diffusivities of liquids over the complete viscosity range even for optically non-transparent samp...
In this paper we demonstrate and discuss the potentials of pulsed field gradient nuclear magnetic resonance (PFG NMR) at high magnetic field and high magnetic field gradients for uncovering the relationship between the structural and transport properties of soft matter systems. The reported diffusion studies are focused on room temperature ionic liquids and their mixtures with carbon dioxide or...
A new class of 4H-imidazoles was synthesized starting from fused-ring aromatic dinitriles. Strong bathochromic shifts of the longest wavelength absorptions were observed in the corresponding UV/vis spectra due to a conversion of the merocyanine chromophores into cyanines/(aza)oxonoles upon protonation/deprotonation of the 4H-imidazoles. Novel boratetraazapentalenes were synthesized via a cycliz...
In the current study, a magnetic inorganic–organic nanohybrid material (HPA/TPI-Fe3O4) was produced and used as an efficient, highly recyclable and eco-friendly catalyst for the one-pot and multicomponent synthesis of 3,4-dihydroquinoxalin-2-amine, diazepine-tetrazole and benzodiazepine-2-carboxamide derivatives with high yields and in a short range of time (20–35 min)...
A number of nucleobase-based barbiturates have been synthesized by combination of nucleic acid bases and heterocyclic amines and barbituric acid derivatives through green and efficient multicomponent route and one pot reaction. This approach was accomplished efficiently using aqueous medium to give the corresponding products in high yield. The newly synthesized compounds were characterized by s...
6-Hydroxy-2-oxo-2H-chromene-4-carbaldehyde (2), 6-chloro-2-oxo-2H-chromene-4-carbaldehyde (3) and 6-hydrazinyl-4-methyl-2H-chromen-2-one (5) were prepared as single-pharmacophore motif key intermediates. Compounds 2, 3 and 5 were incorporated in a series of multicomponent reactions (MCRs), under microwave assistance as well as conventional chemical synthesis processes, to afford a series of thr...
A series of asymmetrically carboxylate-bridged diiron(ii) complexes featuring fluorine atoms as NMR spectroscopic probes, [Fe2(PIM)(Ar(4F-Ph)CO2)2] (10), [Fe2(F2PIM)(Ar(Tol)CO2)2] (11), and [Fe2(F2PIM)(Ar(4F-Ph)CO2)2] (12), were prepared and characterized by X-ray crystallography, Mössbauer spectroscopy, and VT (19)F NMR spectroscopy. These complexes are part of a rare family of syn N-donor dii...
Background: Antioxidants are developed to assist the immune system and overcome oxidative stress, the aggression of cellular constituents due to imbalance between reactive oxygen species and the inner antioxidant system. The main objective of this study was to search for new and potent antioxidants to protect humans against diseases associated with oxidative stress. Methods: In this study, thr...
a one-pot multicomponent reaction of aryl aldehydes, 2-amino benzimidazole and ethyl 2-mercaptoacetate is described as an efficient and environmentally method for the synthesis of some novel ethyl 2-((1h-benzo[d]imidazol-2-ylamino)(aryl)methylthio) acetates in the presence of nano-copper y zeolite (ncz) as a catalyst in ethanol at room temperature. after optimizing of reaction conditions...
An alternative strategy for the synthesis of 1-aryl- and 1-alkyl-2-methylsulfanyl-4-(4-fluorophenyl)-5-(pyridin-4-yl)imidazoles as potential p38α mitogen-activated protein kinase inhibitors is reported. The regioselective N-substitution of the imidazole ring was achieved by treatment of α-aminoketones with different aryl or alkyl isothiocyanates. In contrast to previously published synthesis ro...
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