The Use of Intermediates with Preformed Disulfide Bridge for the Synthesis of Oxytocin and Deamino‐oxytocin

Abstract
The disulfide‐bridged hexapeptides 6a and 6b have been prepared from benzyl‐protected intermediates. Coupling of 6a and 6b with prolyl‐leucyl‐glycine amide afforded deamino‐oxytocin (7a) and the protected oxytocin derivative 7b, respectively; the latter was converted to oxytocin (7c) by removal of the Boc protecting group.