322-30-5Relevant academic research and scientific papers
Structural spectroscopic study of enantiomerically pure synthetic cathinones and their major metabolites
Spálovská, Dita,Pa?kan, Martin,Jurásek, Bronislav,Kucha?, Martin,Kohout, Michal,Setni?ka, Vladimír
supporting information, p. 850 - 860 (2021/01/25)
New psychoactive substances (NPSs) have become a popular alternative to illicit drugs of abuse. However, to determine their metabolic pathways in the human organism, a detailed knowledge of their structure is crucial. Here, we present a comprehensive spectroscopic structural study of synthetic cathinones (clephedrone, flephedrone, and brephedrone) and their major human metabolites, desmethyl derivatives. Chiral high-performance liquid chromatography was utilized to obtain the individual enantiomers of the parent synthetic cathinones and their assumed major metabolites synthesized de novo. The developed chromatographic method made it possible to obtain the target optically pure substances on a multimilligram scale. Electronic and vibrational circular dichroism, combined with infrared and ultraviolet spectroscopy and supported by DFT calculations, were used to determine their absolute configuration and the chiroptical methods to elucidate their molecular structure in detail. Two stable conformers of each substance were found in aqueous solution. Their relative abundances were estimated based on the Boltzmann distribution and the population weighted spectra were obtained. Very good agreement was achieved between the experimental and simulated spectra, enabling the 3D structures of the studied substances to be determined in aqueous solution. This journal is
N.C.A. 18F-labelled norephedrine derivatives via α-aminopropiophenones
Ermert,Hamacher,Coenen
, p. 1345 - 1363 (2007/10/03)
N-protected 2-amino-1-([18F]fluorophenyl)-1-propanones are interesting fluorine-18 labelled intermediates to synthesize potential PET-tracers for mapping the adrenergic nervous system of the heart. Several N-protected α-aminoalkylarylketones were prepared to examine the direct nucleophilic n.c.a. 18F-fluorination of these carbonyl activated precursors. The influence of different protecting groups, the kind of leaving group and the stereoselective reduction of the keto function have been investigated in order to optimize the radiotracer production. It was shown that the 18F-substitution of the para-trimethylammonium group, e.g. of N-dibenzylated propiophenone, leads to radiochemical yields of up to 60%. The stereoselective reduction of the carbonyl function with formation of the n.c.a. erythro 2-N,N-dibenzylamino-1-(4-[18F]fluorophenyl)-1-propanol was performed using BH3·THF. The diastereomeric excess was about 80%. Hydrogenolytical debenzylation was achieved with ammonium formiate in presence of palladium on charcoal to give the 4-[18F]fluoronorephedrine with a radiochemical yield of 15-20% within a total time of 60 min.
