Patent ID: 7645858

Claim:
A method for synthesizing a given peptide or its derivative, which peptide or derivative contains a proline residue or hydroxyproline residue, at or adjacent to the C-terminal end of said peptide, the method comprising the steps of: a) synthesizing on a first resin a C-terminal portion of said peptide, or its derivative, comprising successive coupling of a first amino acid as the C-terminal amino acid residue to the first resin and subsequently coupling at least two successive amino acids to said C-terminal amino acid residue, wherein said C-terminal amino acid residue or the amino acid residue adjacent thereto is a proline residue or a hydroxyproline residue, and said first resin is a 2-chlorotrityl chloride resin; b) cleaving the C-terminal portion thus obtained from said first resin; c) reattaching said C-terminal portion to a second resin, wherein said second resin is a Wang resin or a 4-(3-methoxy-4-(hydroxymethyl)phenoxymethyl) derivative of polystyrene-co-divinylbenzene; and d) coupling selected amino acids, small peptides or derivatives thereof to the C-terminal portion to obtain said given peptide or its derivative.