Stereo-Controlled Asymmetric Bioreduction of α,β-Dehydroamino Acid Derivatives
作者:Clemens Stueckler、Christoph K. Winkler、Mélanie Hall、Bernhard Hauer、Melanie Bonnekessel、Klaus Zangger、Kurt Faber
DOI:10.1002/adsc.201100042
日期:2011.5.9
α,β‐Dehydroamino acidderivatives proved to be a novel substrate class for ene‐reductases from the ‘old yellow enzyme’ (OYE) family. Whereas N‐acylamino substituents were tolerated in the α‐position, β‐analogues were generally unreactive. For aspartic acidderivatives, the stereochemical outcome of the bioreduction using OYE3 could be controlled by variation of the N‐acyl protective group to furnish
Reactivity of Conjugated Phosphazenes Derived from Dehydroaspartic Esters with Acyl Halides. Synthesis of 5(4H)-Oxazolone
作者:Francisco Palacios、Marta Legido、Itziar Perez de Heredia、Gloria Rubiales
DOI:10.3987/com-99-s130
日期:——
The reactivity of N-vinylic phosphazenes derived from dehydroaspartic esters towards acyl halides is reported. Treatment of conjugated phosphazene with acyl halides led to the formation of N-acylated dehydroaspartic esters and alkenyl-5(4N)-oxazolones. When the reaction was performed in the presence of diethylamine, 1-diethylamino-3,4-dimethoxycarbonyl-2-aza-1,3-butadiene was obtained. Reaction of substituted 5(4H)-oxazolones with water, ethanol and amines gave N-acylated dehydroaspartic acid derivatives.
An Effective Synthesis of α,β-Dehydro-α-amino Acid Derivatives from<i>N</i>-Acyl-<i>N</i>-hydroxy-α-amino Acid Esters