Method for synthesis of Tyr-3-octreotide

摘要

The present invention is a novel synthesis of Tyr-3-octreotide for radiopharmaceuticals. In this method, the starting material, Fmoc-Cys(Trt)-Wang Resin, is coupled with various selected amino acids to form a straight chain of peptide-resin compound, D-Phe-Cys(Trt)-Tyr(tBu)-D-Trp(Boc)-Lys(Boc)-Thr(tBu)-Cys(Trt)-Wang Resin. This compound then reacts with iodine to give disulfide-containing peptide resin of <IMAGE> Cleavage of the peptide from the resin is achieved by aminolysis with threoninol, the cleavaged peptide is further deprotected with trifluoroacetic acid (TFA) to obtain the crude peptide Tyr-3-octreotide of the formula <IMAGE> which can be purified by high performance liquid chromatography (HPLC). The final product Tyr-3-octreotide can be labelled by radioiodine for tumor imaging radiopharmaceuticals.