Synthesis of an octacosapeptide amide corresponding to the entire amino acid sequence of chicken vasoactive intestinal polypeptide (VIP).

The octacosapeptide amide corresponding to the entire amino acid sequence of chicken vasoactive intestinal polypeptide (VIP) was synthesized using a new arginine derivative, NG-mesitylene-2-sulfonylarginine. A great tendency of ring closure in the Asp-Asn sequence during the acidolytic deprotection was noted.