The molecule is oxytocin in which the hydrogen on the phenolic hydroxy group is substituted by methyl, the amino group on the cysteine residue is substituted by hydrogen, and the sulfur of the cysteine residue is replaced by a methylene group. A synthetic carba-analogue of oxytocin, it is used to control bleeding after giving birth. Like oxytocin, it causes contraction of the uterus. It has a role as an oxytocic.
(2S)-N-[(2S)-1-[(2-amino-2-oxoethyl)amino]-4-methyl-1-oxopentan-2-yl]-1-[(3R,6S,9S,12S,15S)-6-(2-amino-2-oxoethyl)-9-(3-amino-3-oxopropyl)-12-[(2S)-butan-2-yl]-15-[(4-methoxyphenyl)methyl]-5,8,11,14,17-pentaoxo-1-thia-4,7,10,13,16-pentazacycloicosane-3-carbonyl]pyrrolidine-2-carboxamide