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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 ?-amino acids with EDCI, 1, and NaHCO3 in water or DMF-water media, amide-forming reactions of N-acyl-protected ?-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 ?-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.

SUBMITTER: Mitachi K

PROVIDER: S-EPMC4820766 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Oxyma-based phosphates for racemization-free peptide segment couplings.

Mitachi Katsuhiko K Kurosu Yuki E YE Hazlett Brandon T BT Kurosu Michio M

Journal of peptide science : an official publication of the European Peptide Society 20160301 3

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. Diethyl ...[more]

PMID: 26856693

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