- Bianthryl-based organocatalysts for the asymmetric Henry reaction of fluoroketones
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We have developed a catalytic system based on bianthrylbis(thiourea) for the asymmetric Henry reaction of fluoroketones and nitroalkanes that resulted from the screening of a library containing 31 chiral non-racemic organocatalysts. The corresponding adducts were isolated in up to 6 times shorter reaction time in comparison with the previously published organocatalysts. High levels of stereocontrol have been generally observed, with measured product enantiomeric excesses up to 97% and diastereomeric ratio 3:2 (anti/syn). The above-mentioned catalysts have been successfully applied to the total asymmetric synthesis of CF3-tethered (S)-halostachines, which has proved that this method constitutes an easy entry to similar enantiopure compounds.
- Otevrel, Jan,Svestka, David,Bobal, Pavel
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supporting information
p. 5244 - 5248
(2019/06/07)
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- Synthesis of 2'-arylazabicyclo-3-spiro-4'(5')-imidazolines
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A method is described for the synthesis of a series of 2'-aryl-3-azabicyclospiro-4'(5')-imidazolines via the reaction of azabicyclic 1,2-diamines with aryl imidate salts. Competing reactions in the synthesis of the diamines such as the reduction of amino nitriles with LiAlH4 lead to some anomalous products. In the Pinner synthesis, unstable pyridine-type imidates were stabilized as their N-oxide derivatives.
- Whelan,Iriepa,Galvez
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p. 832 - 836
(2007/10/02)
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- Pyrazolo[1,5-a]pyridine-3-carboxylic acid derivatives and their pharmaceutical use
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Described herein are pyrazolo[1,5-a]pyridine-3-carboxylic acid derivatives represented by the following formula (I): STR1 wherein R 1 and R 2 individually mean a hydrogen atom or a lower alkyl group, R 3 denotes an azabicyclo group containing a tertiary nitrogen atom, and Y stands for --O-- or --NH--, or salts thereof. Their preparation process and serotonin receptor antagonists containing them as active ingredients are also described.
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- Heterocyclic compounds useful as 5-HT3 antagonists
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Aroyl ureas and carbamic acid derivatives of formula and pharmaceutically acceptable salts thereof wherein A is a specified aromatic radical including optionally substituted phenyl W is O or S Y is NH or S and B is a specified saturated azacyclic ring, eg tropan-3-yl or quinuclidin-3-yl, possess 5-HT3 -antagonistic activity and are, for example, useful in treatment of migraine, emesis, anxiety, gastro-intestinal disorders and as anti-psychotics.
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- Fused imidazoheterocyclic compounds and pharmaceutical compositions
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Imidazoheterocyclic compounds having the formula: STR1 wherein the A ring is pyridine in any of its four positions; B is carbonyl, thioxomethyl or hydroxymethylene; Z is hydrogen, halogen, loweralkyl, hydroxy, loweralkoxy, diloweralkylamino or nitro; Ar i
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