title: Formation and rearrangement of homoserine depsipeptides and depsiproteins in the α-ketoacid-hydroxylamine ligation with 5-oxaproline.
abstract: The primary products of the chemical ligation of α-ketoacids and 5-oxaproline peptides are esters, rather than the previously reported amides. The depsipeptide product rapidly rearranges to the amide in basic buffers. The formation of esters sheds light on possible mechanisms for the type II KAHA ligations and opens an avenue for the chemical synthesis of depsiproteins.
authors.affiliation: Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich (Switzerland) http://www.bode.ethz.ch.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Wucherpfennig
authors.forename: Florian
authors.initials: F
authors.lastname: Rohrbacher
authors.forename: Vijaya R
authors.initials: VR
authors.lastname: Pattabiraman
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Bode
mesh_terms: D000595:Amino Acid Sequence; D006898:Hydroxylamines / Q000737:chemistry*; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry*; D011392:Proline / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D006898:Hydroxylamines; D009842:Oligopeptides; C057984:5-oxaproline; D011392:Proline
keywords: chemoselectivity; depsipeptides; ligation; proteins; reaction mechanisms