Analogues of neurohypophysial hormones, containing tert-leucine: Synthesis and properties

Abstract

Analogues of oxytocin, deamino-oxytocin and deamino-vasopressin, containing tert-leucine in position 8, were prepared by fragment condensation in solution. Stepwise synthesis in solution afforded analogues of 1-carba- and 6-carba-deamino-oxytocin with tert-leucine in position 2. [8-Tert-leucine]oxytocin proved to be the most interesting of this series; it exhibits a relatively high and specific galactogogic activity and is cleaved with chymotrypsin by an order of magnitude more slowly than oxytocin.