Solid phase synthesis of somatostatin-28

The synthesis of ovine hypothalamic somatostatin-28 (Ser-Ala-Asn-Ser-Asn-Pro-Ala-Met-Ala-Pro-Arg-Glu-Arg-Lys-Ala-Gly-$\text{Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys}$-OH) has been accomplished by solid phase methodology. The structure of the synthetic material was verified by: (1) direct sequence analysis with a Beckman 89°C sequencer, (2) correlation of the amino acid analyses of the isolated tryptic peptide fragments with their theoretical compositions, and (3) comparison, using high performance liquid chromatography, of the synthetic methionine-sulfoxide and methionine-sulfone modified NH₂-terminal peptides (residues 1–11) with the corresponding tryptic fragment from somatostatin-28.