Synthesis of enantiomerically enriched (R)-13C-labelled 2-aminoisobutyric acid (Aib) by conformational memory in the alkylation of a derivative of L-alanine
نویسندگان
چکیده
The method of Kouklovsky and coworkers for the enantioselective alkylation of cyclic N-naphthoyl derivatives of amino acids was used to introduce a (13)C label into one of the two enantiotopic methyl groups of 2-aminoisobutyric acid (Aib) by retentive alkylation of L-alanine with (13)CH(3)I. Conditions were identified for optimization of yield and enantiomeric purity, and the absolute configuration of the labelled product was established.
منابع مشابه
Chemoenzymatic synthesis of polypeptides containing the unnatural amino acid 2-aminoisobutyric acid.
Polypeptides containing 2-aminoisobutyric acid (Aib) units as an unnatural amino acid residue were synthesized by papain-catalyzed chemoenzymatic polymerization of a tripeptide ethyl ester l-Ala-Aib-l-Ala-OEt in an aqueous medium. The Aib-containing polypeptide adopted an α-helix conformation in both the solid and solution phases, which was induced by the periodic Aib residue.
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