A new route was described to synthesize Arg-Gly-Asp-X(RGDX, X=amino acid) tetrapeptide. To better understand the method, the tetrapeptide Arg-Gly-Asp-CySS(RGDCySS) was chosen as a model target for X. First, GDCySS was obtained in four steps, comprising the chloroacetylation of L-aspartic acid(ClCH(2)COAsp), synthesis of chloroacetyl L-aspartic acid anhydride[ClCH(2)COAsp(CO)(2)O], formation of ClCH(2)COAsp-CySS and ammonolysis of ClCH(2)COAsp-CySS. Second, preparation of Arg-NCA, which was coupled with GDCySS to synthesize RGDCySS by the NCA method(Leuchs" anhydrides method, NCA: N-carboxy-alpha-amino acid anhydride). The purity of the product was analyzed by the high performance liquid chromatography(HPLC). Molecular weights of the peptide products were confirmed by mass spectroscopy. In the developed approach, less protected amino acids were used compared to conventional solid-phase synthesis. The new route offers advantages of low cost, simplicity and rapid synthesis with a reasonable yield of 63.0%(calculated according to arginine content).
[1]Jilin Univ, Coll Life Sci, Key Lab Mol Enzymol & Engn, Minist Educ, Changchun 130012, Peoples R China.
[2]Jilin Univ, Hosp 1, Dept Neurosurg, Changchun 130021, Peoples R China.
[3]Jilin Univ, Hosp 2, Changchun 130041, Peoples R China.
(8.0+极速模式)