1: (S)-9-(allyloxy)-8-[bis((tert-butoxy)carbonyl)amino]-9-oxonon-4-enoic acid With benzotriazol-1-ol; O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate; N-ethyl-N,N-diisopropylamine in dichloromethane; N,N-dimethyl-formamide 24.5 h; Inert atmospheresolid phase reaction; 2: With trifluoroacetic acid in dichloromethane 1.08333 h; solid phase reaction; 3: N-Boc-N,O-dimethyl-3-bromotyrosine; N2-[(1,1-Dimethylethoxy)carbonyl]-L-glutamine; N-(fluoren-9-ylmethoxycarbonyl)-L-Val; fmoc-L-Ile-OH; N-Fmoc-L-threonine-OH; Fmoc-citrulline; butyric acid Further stages;