Abstract: In order to synthesize long acting bio-active peptides, some novel unnatural amino acid with chelating functional group were designed and synthesized, and were used in the solid phase synthesis of LHRH analogues. The purity of peptide was analyzed by HPLC and the structure of peptide was confirmed by ESI-MS. The experiment result shows that these unnatural amino acids could be successfully used in the solid phase synthesis of peptides as novel monomers. LHRH antagonists with functional groups show a longer duration of action and half-lives than that of model peptide in vivo and in vitro respectively.

Key words: Chelating functional group, Unnatural amino acid, Bio-active peptide