Solid phase synthesis and biological activities of oxytocin carba analogues containing threonine in position 4

Abstract
Solis phase methodology was developed for the synthesis of carba-analogues of oxytocin. Two known compounds (deamino-1-carba-oxytocin (I) and deamino-6-carba-oxytocin (II)) and two new analogues ([4-threonine]deamino-1-carba-oxytocin (III) and [4-threonine]deamino-6-carba-oxytocin (IV)) were synthesized using different approaches. The latter two compounds were found to possess high biological activity in the rat uterotonic (in vitro and in vivo) and galactogogic (in vivo) assays.