13048-66-3Relevant articles and documents
Reactions of coordinated ligands. XX. Cobalt (3)-promoted hydrolysis of glycine t-butyl ester.
Wu,Busch
, p. 3326 - 3332 (1970)
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Stable carbon isotope analysis of amino acid enantiomers by conventional isotope ratio mass spectrometry and combined gas chromatography/isotope ratio mass spectrometry
Silfer,Engel,Macko,Jumeau
, p. 370 - 374 (1991)
The application of a combined gas chromatography/isotope ratio mass spectrometry (GC/IRMS) method for stable carbon isotope analysis of amino acid enantiomers is presented. This method eliminates the numerous preparative steps integral to the isolation of amino acids and amino acid enantiomers from protein hydrolyzates that precede δ13C analysis by conventional isotope ratio mass spectrometry. Unlike hydrocarbons, amino acids require derivatization prior to GC/ IRMS analysis. Replicate δ13C analyses of trifluoroacetyl (TFA) isopropyl ester derivatives of 22 amino acids by IRMS revealed that the derivatization process is reproducible, with an average error (1 standard deviation) of 0.10‰ ± 0.09 ‰. The average analytical error for analysis of amino acid derivatives by GC/IRMS was 0.26‰ ± 0.09‰. In general, absolute differences between IRMS and GC/IRMS analyses were less than 0.5‰. The derivatization process introduces a distinct, reproducible isotopic fractionation that is constant for each amino acid type. The observed fractionations preclude direct calculation of underivatized amino acid δ13C values from their respective TFA isopropyl ester δ13C compositions through mass balance relationships. Derivatization of amino acid standards of known stable carbon isotope compositions in conjunction with natural samples, however, permits computation of the original, underivatized amino acid δ13C values through use of an empirical correction for the carbon introduced during the derivatization process.
A cation-directed two-component cascade approach to enantioenriched pyrroloindolines
Wolstenhulme, Jamie R.,Cavell, Alex,Grediak, Matija,Driver, Russell W.,Smith, Martin D.
supporting information, p. 13585 - 13588 (2015/02/19)
A cascade approach to complex pyrroloindolines bearing all-carbon quaternary stereocentres has been developed. This two-component process uses a chiral ammonium salt to control diastereo- and enantioselectivity in the addition of isocyanides to functionalized alkenes to afford pyrroloindolines with up to three stereocentres. A mechanistic proposal involving intramolecular hydrogen bond activation of the isocyanide is described.
One-pot conversion of t-butyl carbamates to amides with acyl halide-methanol mixtures
Nazih, Abdesslame,Heissler, Denis
, p. 203 - 206 (2007/10/03)
Acyl halide-methanol mixtures are efficient reagents for the one-pot transformation of t-butyl carbamates into amides. This transformation can be carried out in the presence of a benzyloxycarbonyl group.