The important intermediate, heptapeptide, was synthesized by the stepwise elongation method using carbobenzoxy amino acid p-nitrophenyl esters by solution technique. Azide synthesis was used to get the nonapeptide. 先用逐步增长方式采用对硝基苯酚酯法缩合得到重要中间体七肽片段,再用叠氮法缩合得到保护九肽。