116430-80-9 Krds peptide Krds tetrapeptide L-Serine, N-(N-(N2-L-lysyl-L-arginyl)-L-alpha-aspartyl)- Lys-arg-asp-ser Lysine-arginine-aspartic acid-serine N-(N-(N(Sup 2)-L-lysyl-L-arginyl)-L-alpha-aspartyl)-L-serine