Abstract
Protected dipeptides were obtained in good yield by coupling Boc- or Fmoc-protected amino acids with amino acid esters in the presence of pentafluorophenyl 4-nitrobenzenesulfonate (PFNB) as peptide coupling agent and 1-hydroxybenzotriazole as catalyst.
ACKNOWLEDGMENTS
We acknowledge financial support from the Department of Chemistry and Rachadaphisek Somphot Endowment (grants for development of new faculty staff) from Chulalongkorn University. We also thank the Research Equipment Centre, Chulalongkorn University, for microanalysis service.