18917-24-3 59300-64-0 CCK-5 Cholecystokinin pentapeptide Gly-trp-met-asp-phe-NH2 Glycyl-tryptophyl-methionyl-aspartyl-phenylalaninamide L-Phenylalaninamide, glycyl-L-tryptophyl-L-methionyl-L-alpha-aspartyl-