The reaction of symmetrical (thio)barbituric acids with aldehydes in the presence of 4-methyl morpholine yielded a new form of 4-methyl morpholinium bis-(thio)barbiturate containing charge-separated intermolecular and eightmembered intramolecular H-bonds. X-ray Crystallography, FT-IR, and 1 H and 13 C-NMR spectroscopy techniques were used for structure characterizations. Some of these compounds showed potent anticancer activities. Cytotoxicity of the synthetic compounds against HeLa and MCF-7 cell lines were performed by MTT assay. In addition, a comparative molecular field analysis was carried out, and the effects of substituents on the biological activities of these compounds were explained.
A new route for the synthesis of 2-alkanoyl(aryloyl)-5,5-dimethylcyclohexane-1,3-diones as cyclic β-triketones is described. This synthesis was conducted by the reaction of dimedone with cyanogen bromide and triethylamine to form first the intermediate salt, followed by the addition of various aliphatic and aromatic aldehydes. The structures of the products were characterized by IR, 1 H, and 13 C NMR spectroscopic techniques. A reaction mechanism is proposed.
Aims & scope MRC is devoted to the rapid publication of papers which are concerned with the development of magnetic resonance techniques, or in which the application of such techniques plays a pivotal part. Contributions from scientists working in all areas of NMR, ESR and NQR are invited, and papers describing applications in all branches of chemistry, structural biology and materials chemistry are published. The journal is of particular interest not only to scientists working in academic research, but also those working in commercial organisations who need to keep up-to-date with the latest practical applications of magnetic resonance techniques. 54(5) 347-414 (2016) ISSN 0749-1581 347 Q.E.COSY: determining sign and size of small deuterium residual quadrupolar couplings using an extended E.COSY principle 351-357 P. Tzvetkova and B. Luy The Q.E.COSY as an extension of the E.COSY principle allows the sign sensitive measurement of residual quadrupolar couplings in partially aligned samples even in cases where corresponding splittings are not resolved in the deuterium 1D spectrum. Several experimental demonstrations are given. Isotopic splitting patterns in the 13 C nuclear magnetic resonance spectra of some partially deuterated 1-aryl-2-(phenyldiazenyl)butane-1,3-dione and 4-hydroxy-3-(phenyldiazenyl)-2H-chromen-2-one were investigated: CDCl 3 and/or DMSO-d6 with addition of two drops of D 2 O. All dyes showed intramolecular hydrogen bonding. Among ten dye samples, two dyes derived from benzoylacetone did not show deuteration, three dyes showed partial deuteration and five dyes showed full deuteration under similar conditions. wileyonlinelibrary.com/journal/mrc MRC Contents continued overleaf Contents continued Hopping and residence times of water on biochar surface have been measured by fast field cycling NMR relaxometry. These were related to biochar wettability. NMR results accorded with those from contact angle measurements, thereby indicating that the former technique is a valid alternative to the latter. Advantage of relaxometry over contact angle measurements lies in the possibility to obtain not only wettability, but also mechanisms of water molecular dynamics on biochar surface, thereby leading to the understanding of its role in increasing soil quality and plant nutrition. Evaluation of the surface affinity of water in three biochars using fast field cycling NMR relaxometry 365-370
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.