341926-08-7Relevant academic research and scientific papers
Practical synthesis of enantiomerically pure β2-amino acids via proline-catalyzed diastereoselective aminomethylation of aldehydes
Chi, Yonggui,English, Emily P.,Pomerantz, William C.,Horne, W. Seth,Joyce, Leo A.,Alexander, Lane R.,Fleming, William S.,Hopkins, Elizabeth A.,Gellman, Samuel H.
, p. 6050 - 6055 (2008/02/08)
Proline-catalyzed diastereoselective aminomethylation of aldehydes using a chiral iminium ion, generated from a readily prepared precursor, provides α-substituted-β-amino aldehydes with 85:15 to 90: 10 dr. The α-substituted-β-amino aldehydes can be reduce
CONCISE BETA2-AMINO ACID SYNTHESIS VIA ORGANOCATALYTIC AMINOMETHYLATION
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Page/Page column 14; 32; 39; 42; 45-46, (2010/11/28)
The present invention provides a method for the synthesis of ?2-amino acids. The method also provides methods yielding a-substituted ?-amino aldehydes and ?-substituted γ-amino alcohols. The present method according to this invention allows for increased yield and easier purification using minimal chromatography or crystallization. The methods described herein are based on an aldehyde aminomethylation which involves a Mannich reaction between an aldehyde and a formaldehyde-derived N,O-acetal (iminium precursor) and a catalyst, such as, for example, L-proline or a pyrrolidine. The invention allows for large scale, commercial preparation of ?2-amino acids.
Expanding the utility of proteases in synthesis: Broadening the substrate acceptance in non-coded amide bond formation using chemically modified mutants of subtilisin
Khumtaveeporn, Kanjai,Ullmann, Astrid,Matsumoto, Kazutsugu,Davis, Benjamin G.,Jones
, p. 249 - 261 (2007/10/03)
The strategy of combined site directed mutagenesis and chemical modification creates chemically modified mutants (CMMs) with greatly broadened substrate specificities. We have previously reported that the CMMs of subtilisin Bacillus lentus (SBL) are efficient catalysts for the coupling of both L- and D-amino acids. We now report that these powerful catalysts also allow amide bond formation between a variety of non-coded carboxylic acids, including β-alanine and β-amino homologues of phenylalanine, with both L- and D-amino acid nucleophiles. As a guide to enzyme efficiency, a hydrolysis assay indicating pH change has been employed. CMMs selected by this screen furnished higher yields of coupling products compared to the wild-type enzyme (WT). Furthermore, both WT and CMM enzymes allow highly stereoselective aminolysis of a meso diester with an amino acid amine. These results highlight the utility of CMMs in the efficient formation of non-coded amides as potential peptide isosteres.
