159707-18-3Relevant articles and documents
Synthesis of α-amino acids through samarium(II) iodide promoted reductive coupling of nitrones with CO2
Prikhod'Ko, Alexander,Walter, Olaf,Zevaco, Thomas A.,Garcia-Rodriguez, Jaime,Mouhtady, Omar,Py, Sandrine
supporting information; experimental part, p. 3742 - 3746 (2012/09/25)
Several N-benzylnitrones reacted with carbon dioxide in the presence of samarium(II) iodide leading to α-amino acids as the products of reductive C-C coupling. The best selectivities were observed at a carbon dioxide pressure of 50 bar at ambient temperature. The influences of different functional groups in the nitrone backbone and of the coordinating additives to samarium(II) iodide on the product distribution were investigated. The racemic α-amino acids were obtained in up to 70% yield based on HPLC data. A novel approach to the synthesis ofα-amino acids is disclosed, involvingC-carboxylation of nitrones by gaseous CO2 under reductive coupling reaction conditions (SmI2, 0.1 M in THF) at ambient temperature and 50 bar of CO 2 pressure. Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Polymorphic form of a tachykinin receptor antagonist
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, (2008/06/13)
This invention is concerned with a novel polymorphic form of the compound 2-(R)-(1-(R)-(3,5-bis(trifluoromethyl)-phenyl)-ethoxy)-3-(S)-(4-fluoro)phenyl-4-(3-(5-oxo-1H,4H-1,2,4-triazolo)methylmorpholine which is a tachykinin receptor antagonist useful in the treatment or prevention of disorders of the central nervous system, inflammatory diseases, pain or migraine, asthma, and emesis. The instant polymorphic form has advantages over the other known forms of 2-(R)-(1-(R)-(3,5-bis(trifluoro-methyl)-phenyl)ethoxy)-3-(S)-(4-fluoro)phenyl-4-(3-(5-oxo-1H,4H-1,2,4-triazolo)methylmorpholine in terms of thermodynamic stability and suitability for inclusion in pharmaceutical formulations.
Syntheses of optically active α-amino nitrites by asymmetric transformation of the second kind using a principle of O. Dimroth
Hassan, Nasser A.,Bayer, Erwin,Jochims, Johannes C.
, p. 3747 - 3757 (2007/10/03)
A mixture of solids As and Bs in equilibrium with the dissolved compounds A1 and B1 is transformed completely into one pure solid, say Bs, if the dissolved compounds A1?B1 are equilibrating in solution. This is applied to transform 1:1 mixtures of solid diastereomeric amygdalates (2-hydroxy-2-phenylacetates; mandelates) (R,R)-3 + (S,R)-3 prepared from racemic α-amino nitriles (R,S)-1 with (R)-mandelic acid 2 into stereochemically pure single diastereomers (R,R)-3, or (S,R)-3 (de > 97%) ('asymmetric transformation of the second kind by application of Dimroth's principle'). Decomposition of the amygdalates (R,R)-3, or (S,R)-3, with aqueous base affords the enantiomerically pure α-amino nitriles (A)-1, or (S)-1 (ten examples). The chiral auxiliary (R)-mandelic acid is recovered almost quantitatively. The optically active α-amino nitriles are hydrolyzed to amides 6, and further to α-N-alkylamino acids 7. N-Benzylamino acids 7 are hydrogenated to α-amino acids 8. Some of the optically active α-amino nitriles 1 are reduced to optically active 1,2-diamines 9. In most cases, absolute configurations could be assigned by comparison of the specific rotations observed with those of authentic compounds.
