Synthesis of [1-(L-2-hydroxy-3-mercaptopropanoic acid)]oxytocin, a highly potent analogue of oxytocin

Abstract

An analogue of oxytocin containing a hydroxy-group in place of the primary amino-group was synthesized by coupling p-nitrophenyl L-2-acetoxy-3-benzylthiopropanoyl-L-tyrosinate with a heptapeptide. [1-(L-2-Hydroxy-3-mercaptopropanoic acid)]oxytocin possessed three times the oxytocic activity of oxytocin on the isolated rat uterus. Neurophysin did not bind the new analogue.