title: Oxyma-based phosphates for racemization-free peptide segment couplings.
abstract: Glyceroacetonide-Oxyma [(2,2-dimethyl-1,3-dioxolan-4-yl)methyl 2-cyano-2-(hydroxyimino)acetate (1)] displayed remarkable physico-chemical properties as an additive for peptide-forming reactions. Although racemization-free amide-forming reactions have been established for N-urethane-protected α-amino acids with EDCI, 1, and NaHCO3 in water or DMF-water media, amide-forming reactions of N-acyl-protected α-amino acids and segment couplings of oligopeptides still require further development. Diethylphosphoryl-glyceroacetonide-oxyma (DPGOx 3) exhibits relative stability in aprotic solvents and is an effective coupling reagent for N-acyl-protected α-amino acids and oligo peptide segments. The conditions reported here is also effective in lactam-forming reactions. Unlike most of the reported coupling reagents, simple aqueous work-up procedures can remove the reagents and by-products generated in the reactions.
authors: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN, 38163-0001, USA.
authors: Katsuhiko
authors: K
authors: Mitachi
authors: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN, 38163-0001, USA.
authors: Yuki E
authors: YE
authors: Kurosu
authors: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN, 38163-0001, USA.
authors: Brandon T
authors: BT
authors: Hazlett
authors: Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, TN, 38163-0001, USA.
authors: Michio
authors: M
authors: Kurosu
mesh_terms: D000085:Acetates / Q000737:chemistry*; D000577:Amides / Q000737:chemistry*; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000138:chemical synthesis*; D010091:Oximes / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D013237:Stereoisomerism; D014867:Water / Q000737:chemistry
chemical_list: D000085:Acetates; D000577:Amides; D000596:Amino Acids; D009842:Oligopeptides; D010091:Oximes; D010710:Phosphates; C548311:ethyl 2-cyano-2-(hydroxyimino)acetate; D014867:Water
keywords: Oxyma; diethylphosphoryl-Glyceroacetonide-Oxyma; lactam-forming reactions; peptide synthesis; segment coupling