Ferric chloride induced dehydrodimerization of l,2 ,3 ,4 -te trah yd ro-9 //-carb azole (1) gives pro­ duct 6 , the structure of which was established on the basis of its spectroscopic properties. The *H and 13C chemical shifts of the arom atic part of 1 , as well as of 4a-m eth yl-2 ,3 ,4 ,4a-tetrah yd ro-l Hcarbazole (7 a ) and 4a-ph enyl-2 ,3 ,4 ,4a-tetrahyd ro-l//-carb azole (7b ) have also...

The most common means of identification of gamma-hydroxybutyrate (NaGHB) involves using Fourier transform infrared spectroscopy (FTIR) or gas chromatography-mass spectrometry (GC-MS) of a suitable derivative. However, these methods may be complicated by possible shifts in chemical equilibrium between gamma-hydroxybutyric acid (GHB), GHB salts and the precursor lactone, gamma-butyrolactone (GBL)...

The structure of a representative pyrazolo[3,4]pyran derivative was determined by 1D and 2D NMR techniques. Complete 1H and 13C chemical shifts for this compound are reported. Careful analysis of the HMBC (Heteronuclear Multi-Bond Correlation) spectrum helped to elucidate the configuration of the derivative around C7 and C8. The results showed that the characteristic double-strong and double-we...

Density functional theory is demonstrated to reproduce the 13C and 11B NMR chemical shifts of icosahedral boron carbides with sufficient accuracy to extract previously unresolved structural information from experimental NMR spectra. B4C can be viewed as an arrangement of 3-atom linear chains and 12-atom icosahedra. According to our results, all the chains have a CBC structure. Most of the icosa...

We present the spatial architecture of a new anhydrous polymorph of Acyclovir, obtained by rapid evaporation of a solution composed of Acyclovir and methanol. X-ray powder diffraction (XRPD), solid-state NMR (SSNMR), differential scanning calorimetry (DSC), and FTIR spectroscopy have been used as experimental tools to prove the formation of this new solid form and to characterize its crystallin...

The data shown in this article are related to the subject of an article in Carbohydrate Polymers, entitled "Synthesis and characterization of chitosan alkyl urea" [1]. 1H NMR and 13C NMR spectra of chitosan n-octyl urea, chitosan n-dodecyl urea and chitosan cyclohexyl urea are displayed. The chemical shifts of proton and carbon of glucose skeleton in these chitosan derivatives are designated in...

The prediction of 13C chemical shifts can be challenging with density functional theory (DFT). In this study 39 different functionals and three basis sets were tested on neutral alkylpyrroles their corresponding protonated species. calculated shielding constants compared to experimental data results from previous calculations at the MP2. We find that meta-hybrid TPSSh either Pople style set 6-3...

Abstract The 13 C NMR chemical shifts of the three Edaravone tautomers (keto, enol, and amine) were calculated using a combined molecular mechanics (Pcmod 9.1/MMFF94) ab initio (GIAO (B3LYP/DFT, 6–31 + G(d)) model. This method gave such good agreement with experiment that assignment complex spectrum in solution, which is mixture could be made. has been attempted previously by various methods di...

The vibrational fundamental modes of 7-methoxy4-bromomethylcoumarin (7BMC) have been analyzed by combining FTIR, FT-Raman and quantum chemical calculations. The structural parameters of the compound are determined from the optimized geometry by B3LYP method with 6-311++G (d, p) basis set. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experime...