Condensation of (tert-butyloxycarbony1) tccinoic acid with L-prolyl-L-tryptophylglycinamide produced the Boc derivative of a nonapeptide (disulfide) which on deprotection afforded [8-~- tryptophan] oxytocin. In assays on the rat uterus in vitro and in vivo the new analogue acts as both an agonist and an antagonist. The duration of both actions is prolonged.
![benzyl N-[(2S)-1-[(2-amino-2-oxoethyl)amino]-3-(1H-indol-3-yl)-1-oxopropan-2-yl]carbamate Structure](https://image.chemsrc.com/caspic/169/68996-89-4.png)
