Stereoselective synthesis of a set of two functionalized (E)-alkene dipeptide isosteres of L-amino acid-L-Glu and L-amino acid-D-Glu

Treatment of N-arylsulfonyl-γ,δ-cis- or -trans-γ,δ-epimino (E)-α,β-enoates with HCl–1,4-dioxane affords regio- and stereo-selective ring-opened products, δ-aminated γ-chloro-α,β-enoates. This ring-opening reaction provides a useful method for the stereoselective synthesis of a set of diastereomeric (L-Xaa, L-Glu)-type and (L-Xaa, D-Glu)-type (E)-alkene dipeptide isosteres (EADIs) from a single substrate of γ,δ-epimino (E)-α,β-enoate using organozinc–copper reagents.