Amino acids and peptides. XVIII. Dipeptide formation during the synthesis of Z-Asp(OBzl)-OH.
During the benzyloxycarbonylation of H-Asp(OBzl)-OH by the Schotten-Bauman reaction with benzyloxycarbonyl chloride in the presence of NaHCO3 or Na2CO3, besides Z-Asp(OBzl)-OH, Z-Asp(OBzl)-Asp(OBzl)-OH was formed as side product, although the extent of the dipeptide formation differed depending on the base used (10% and 20% respectively). It was found that melting point, rotation value and Rf values upon thin-layer chromatography of Z-Asp(OBzl)-Asp(OBzl)-OH were quite similar to those of Z-Asp(OBzl)-OH.
Faculty of Pharmaceutical Sciences, Kobe-Gakuin University, Japan.
S
S
Iguchi
K
K
Kawasaki
Y
Y
Okada
D000596:Amino Acids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004151:Dipeptides / Q000032:analysis; D009842:Oligopeptides / Q000138:chemical synthesis*
D000596:Amino Acids; D004151:Dipeptides; D009842:Oligopeptides