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NMR Spectroscopic Parameters of Molecular Systems with Strong Hydrogen Bonds
(American Chemical Society, 2010-07)
A series of closed H-bonded molecules that have (or not) delocalized bonds were studied. The dependence of both NMR spectroscopic parameters σ and J-couplings, and also the energy stability of such molecules with H-bond ...
NMR espectroscopic parameters of HX and Si (Sn)X4 (X = H, F, Cl, Br and I) and SnBr4-nIn model compounds
(Elsevier Science, 2012-02)
The NMR spectroscopic parameters are largely influenced by relativistic effects. They are highly dependent on the electronic behavior inside the spatial regions occupied by nuclei. Full relativistic calculations of indirect ...
A detailed experimental and theoretical study of two novel substituted trifluoromethylchromones. The influence of the bulky bromine atom on the crystal packing
(Pergamon-Elsevier Science Ltd, 2015-02)
(Figure Presented) The new 3-methyl-2-trifluoromethylchromone (1 ) and 3-bromomethyl-2-trifluoromethylchromone (2) compounds were synthesized and characterized by vibrational (IR, Raman), UV-Vis and NMR (1H, 13C and 19F) ...
Synthesis, structural and spectroscopic studies of 1-(2-FUROYL)-3- phenylthiourea: a theoretical and experimental approach
(Taylor & Francis Ltd, 2016-09-03)
The thiourea derivative 1-(2-Furoyl)-3-phenylthiourea (FPT) was synthesized and characterized by using spectroscopic (IR, Raman, UV–VIS, 1H and 13C NMR) and structural methods (powder X-ray diffraction data). The experimental ...
New thiourea and urea derivatives containing trifluoromethyl- and bis-triflouromethyl-4H-chromen-3-yl substituents
(Taylor & Francis Ltd, 2019-02)
Two new thiourea (1) and urea (2) derivatives, substituted with 2-trifluoromethyl-4H-chromen-3-yl moieties at defined positions, were obtained by convenient synthetic methodologies. The pure compounds were studied in solid ...
Preparation and characterization of a new solid form of praziquantel, an essential anthelmintic drug: Praziquantel racemic monohydrate
(Elsevier Science, 2020-04)
Praziquantel (PZQ) is a highly effective low-cost anthelmintic agent used as the first-choice treatment against schistosomiasis. The low solubility of the active is a major drawback for pharmaceutical formulation. A valid ...
Pseudocnoside A, a new cytotoxic and antiproliferative triterpene glycoside from the sea cucumber Pseudocnus dubiosus leoninus
(Taylor & Francis, 2012-12-17)
A new triterpene glycoside, pseudocnoside A (1), was isolated from the sea cucumber Pseudocnus dubiosus leoninus. The structure of the new compound was established on the basis of extensive NMR spectroscopic analysis (1H ...
Partial and total C-6 oxidation of gelling carrageenans. Modulation of the antiviral activity with the anionic character
(Elsevier, 2015-09)
The optimal conditions for the full C-6 oxidation of - and -carrageenans using (2,2,6,6- tetramethylpiperidinyl)oxy (TEMPO) in the presence of sodium hypochlorite and sodium bromide were assessed. The fully oxidized products ...