Adrenocorticotropin. 49.1 Synthesis and biological activity of [2-delta-aminovaleric acid, 5-arginine-a1adrenocorticotropin-(2-19).

An adrenocorticotropin analogue, [2-delta-aminovaleric acid, 5-arginine]adrenocorticotropin-(2-19), has been synthesized by the solid-phase method and its biological activity has been determined. It was found that substitution of arginine for glutamic acid at position 5 of [2-delta-aminovaleric acid]adrenocorticotropin-(2-19) increased the steroidogenic potency in idolated rat adrenal cells and the lipolytic potency in isolated rat fat cells but decreased the lipolytic potency in isolated rabbit fat cells. The synthetic analogue had only 2% of the melanotropic potency of the parent molecule.