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Selective access to E- and Z-ΔIle-containing peptides via a stereospecific E2 dehydration and an O → N acyl transfer. | LitMetric

A concise synthesis of peptides that contain E- or Z-dehydroisoleucine (ΔIle) residues is reported. The key reaction is an unusual anti dehydration of β-tert-hydroxy amino acid derivatives that is mediated by the Martin sulfurane. A subsequent tandem Staudinger reduction-O → N acyl transfer process forges an amide bond to the ΔIle residue with minimal E/Z alkene isomerization. Density functional calculations attribute the stereospecific dehydration to a highly asynchronous E2 anti process.

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Source
http://dx.doi.org/10.1021/ol5018933DOI Listing

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