title: Improved synthesis of C-terminal peptide thioesters on "safety-catch" resins using LiBr/THF.
abstract: [reaction: see text] The alkanesulfonamide "safety-catch" resin has proven useful for Fmoc-based synthesis of C-terminal peptide thioesters. We now report that the yield of isolated thioester can increase significantly when the cleavage reaction is carried out in 2 M LiBr/THF rather than DMF or THF. The largest effects are seen with problematic peptides that aggregate or form secondary structures on the resin.
authors.affiliation: Laboratory of Organic Chemistry, Swiss Federal Institute of Technology (ETH), Universitätstrasse 16, CH-8092 Zürich, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Quaderer
authors.forename: D
authors.initials: D
authors.lastname: Hilvert
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D007611:Aprotinin / Q000138:chemical synthesis*; D001965:Bromides / Q000737:chemistry; D002417:Cattle; D005449:Fluorenes / Q000737:chemistry; D005663:Furans / Q000737:chemistry; D018020:Lithium Compounds / Q000737:chemistry; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis*; D012116:Resins, Plant / Q000737:chemistry*; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D001965:Bromides; D005449:Fluorenes; D005663:Furans; D018020:Lithium Compounds; C016456:N(alpha)-fluorenylmethyloxycarbonylamino acids; D010446:Peptide Fragments; D012116:Resins, Plant; D013449:Sulfonamides; C018674:tetrahydrofuran; C040949:lithium bromide; D007611:Aprotinin