The structures of two neutral and 17 salt forms of the base (1R, 2S)-(-)-ephedrine are reported. These structures are discussed in the light of the conformers of the ephedrine moiety, the existence of bilayers and the structure determining role of the counterions. Overall, most of the salt structures are essentially derived from the observed packing of the neutral base and are dominated by the amphiphilic nature of the ephedrine molecular structure. In a few cases the size and hydrophobicity of the counterion disrupts this behaviour.
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http://dx.doi.org/10.1107/S0108768106012018 | DOI Listing |
Faraday Discuss
January 2025
Department of Chemistry & Biochemistry, Florida State University, Tallahassee, FL 32306, USA.
Quadrupolar NMR crystallography guided crystal structure prediction (QNMRX-CSP) is a nascent protocol for predicting, solving, and refining crystal structures. QNMRX-CSP employs a combination of solid-state NMR data from quadrupolar nuclides (, nuclear spin >1/2), static lattice energies and electric field gradient (EFG) tensors from dispersion-corrected density functional theory (DFT-D2*) calculations, and powder X-ray diffraction (PXRD) data; however, it has so far been applied only to organic HCl salts with small and rigid organic components, using Cl EFG tensor data for both structural refinement and validation. Herein, QNMRX-CSP is extended to ephedrine HCl (Eph) and pseudoephedrine HCl (Pse), which are diastereomeric compounds that feature distinct space groups and organic components that are larger and more flexible.
View Article and Find Full Text PDFMolecules
May 2022
Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
The optically active dibenzoyltartaric acid, tartaric acid, and its sodium salts were successfully applied to the optical resolution of (1,2)(1,2)-2-(methylamino)-1-phenylpropan-1-ol () and (1,2)(1,2)-2-amino-1-(4-nitrophenyl)propane-1,3-diol () as resolving agents. It was observed that both compounds' resolution using a mixture of salts of quasi-racemic resolving agents showed a change in chiral recognition under the same conditions compared to the result of the use of the single enantiomeric resolving agent. The changes are followed by detailed analytical (XRD, FTIR, and DSC) studies.
View Article and Find Full Text PDFForensic Sci Int
August 2016
Department of Forensic Chemistry and Toxicology of the State General Laboratory of Ministry of Health, Nicosia 1451, Cyprus.
This is a case report of a fatal intoxication in Cyprus related to 3,4-methylenedioxypyrovalerone (MDPV) and 2-(methylamino)-1-phenylpentan-1-one (pentedrone) intake combined with antipsychotic and antidepressant substances. A 42- year old man with a history of serious psychiatric illness was found unresponsive in his bed. Seized materials were also found close to his body.
View Article and Find Full Text PDFJ Org Chem
June 2015
†Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary.
Three chiral α-(nonafluoro-tert-butoxy)carboxylic acids (R)-1, (RS)-2, (R)-3 were synthesized to examine their application as chiral solvating agents with amines. As a model compound, first (S)- and/or (RS)-α-phenylethylamine was used, and their diastereomeric salts were investigated by (1)H and (19)F NMR and ECD spectroscopy. The NMR spectroscopic studies were carried out at room temperature using the slightly polar CDCl3 and apolar C6D6 as solvents in 5 mM and 54 mM concentrations.
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