Preparation of octreotide and Tyr3-octreotide from Thr(ol)(tBu)-2-chlorotrityl resin

摘要

Octreotide of formula (IA) or (IB) may be prepared by the following steps: 1) coupling selected amino acids with a Thr(ol)(tBu)-2-chlorotrityl resin to give a straight chain peptide resin compound of formula (IIA) or (IIB); 2) cleaving the straight chain peptide from the resin with a TFA, EDT and H2O solution; and 3) oxidizing the straight chain peptide to obtain the disulfide-containing peptide.