Y. Vidal

Diastereoselective radical addition to dehydroalanine derivatives of pantolactone

The diastereoselective synthesis of α-amino acids by radical addition to dehydroalanine derivatives of pantolactone using the stannane method both in the presence and absence of Lewis acid catalysts is reported. The absolute configuration of the newly-generated stereogenic center is highly dependent on the nature of the added radical. Acid hydrolysis afforded the amino acids with excellent yields and without racemization. This approach constitutes a novel method for the asymmetric synthesis of α-amino acids by a radical pathway.

Some of the amino acid chemistry going on in the Laboratory of Amino Acids, Peptides and Proteins

SummarySome of the chemistry of amino acids going on in our laboratory (Laboratoire des Amino acides Peptides et Protéines) is described as well as some mass spectrometry methodology for their characterization particularly on solid supports. Several aspects are presented including: (i) the stereoselective synthesis of natural and unnatural amino acids using 2-hydroxypinan-3-one as chiral auxiliary; (ii) the stereoselective synthesis of natural and unnatural amino acids by deracemization ofα-amino acidsvia their ketene derivatives; (iii) the synthesis ofα-aryl-α-amino acidsvia reaction of organometallics with a glycine cation; (iv) the diastereoselective synthesis of glycosyl-α-amino acids; (v) the synthesis ofβ-amino acids using a-aminopyrrolidinopiperazinediones as chiral templates; (vi) the reactivity of urethane-N-protected N-carboxyanhydrides. To characterize natural and non natural amino acids through their immonium ions by mass spectrometry, some methodology is also described.