32634-66-5Relevant articles and documents
Diquats with Robust Chirality: Facile Resolution, Synthesis of Chiral Dyes, and Application as Selectors in Chiral Analysis
Talele, Harish R.,Koval, Du?an,Severa, Luká?,Reyes-Gutiérrez, Paul E.,Císa?ová, Ivana,Sázelová, Petra,?aman, David,Bednárová, Lucie,Ka?i?ka, Václav,Teply, Filip
, p. 7601 - 7604 (2018)
Diquats with extremely high racemization barriers with ΔG≠theor of 233 kJ mol?1 at 180 °C are described. Reported configurational robustness is due to a combination of two structural features: the rigid o-xylylene tether connecting the nitrogen atoms and the presence of two substituents in the bay region of the bipyridinium scaffold. The straightforward synthesis of diquats, plus facile resolution and derivatization make them attractive for chiral application studies. This is demonstrated by: 1) synthesis of the first non-racemic diquat dyes with pronounced chiroptical properties, and 2) capability of diquats to interact stereospecifically with chiral molecules. This suggests potential for diquat derivatives to be used as chiral selectors in separation methods.
NOVEL RESOLUTION PROCESS FOR PREGABALIN
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Page/Page column 6; 15, (2009/05/29)
Present invention relates to a novel and improved process for the resolution of racemic pregabalin of formula (I) into (S)-(+)-pregabalin [(S)-(+)-3-aminomethyl-5-methylhexanoic acid] of formula (III) via the novel acid addition salt [(S)-(+) 3-aminomethyl-5-methylhexanoic acid, (-)-O, O'-di-p-toluoyl-L-tartaric acid salt] of formula (II). (S)-(+)-pregabalin of formula-III has analgesic, anticonvulsant and anxiolytic properties and hence is of great therapeutic significance.
Novel processes for the preparation of (R)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol
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, (2008/06/13)
The present invention provides various processes for the preparation of (R)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol. These processes may be characterized by the following scheme: