Title: Atosiban
CAS Registry Number: 90779-69-4
CAS Name: 1-(3-Mercaptopropanoic acid)-2-(O-ethyl-D-tyrosine)-4-L-threonine-8-L-ornithineoxytocin
Additional Names: 1-(3-mercaptopropionic acid)-2-[3-(p-ethoxyphenyl)-D-alanine]-4-L-threonine-8-L-ornithineoxytocin; 1-deamino-2-D-tyr-(OEt)-4-thr-8-orn-oxytocin; antocin; dTVT
Manufacturers' Codes: ORF-22164; F-314; RWJ-22164; CAP-440
Trademarks: Tractocile (Ferring)
Molecular Formula: C43H67N11O12S2
Molecular Weight: 994.19
Percent Composition: C 51.95%, H 6.79%, N 15.50%, O 19.31%, S 6.45%
Literature References: Oxytocin antagonist. Prepn: P. O. R. Melin, J. A. Trojnar, EP 112809; eidem, US 4504469 (1984, 1985 both to Ferring). Mechanism of action: A. Lopez Bernal et al., Br. J. Obstet. Gynaecol. 96, 1108 (1989). Effect on in vitro contractility of myometrium: V. A. Kinsler et al., ibid. 103, 373 (1996). Clinical pharmacokinetics: T. M. Goodwin et al., Am. J. Obstet. Gynecol. 173, 913 (1995). Clinical trial: T. M. Goodwin et al., ibid. 170, 474 (1994).
Therap-Cat: Tocolytic.
Keywords: Tocolytic.
Atovaquone Atractyloside Atracurium Besylate Atranorin Atrasentan

Atosiban SW.svg
Systematic (IUPAC) name
1-(3-mercaptopropanoic acid)-
Clinical data
Trade names Tractocile, Antocin
AHFS/ International Drug Names
Legal status  ?
Routes intravenous
CAS number 90779-69-4 N
ATC code G02CX01
PubChem CID 5311010
ChemSpider 4470550 YesY
UNII 081D12SI0Z YesY
KEGG D03008 YesY
Chemical data
Formula C43H67N11O12S2 
Mol. mass 994.199
 N (what is this?)  (verify)

Atosiban (trade names Tractocile, Antocin, atosiban SUN) is an inhibitor of the hormones oxytocin and vasopressin. It is used as an intravenous medication as a labour repressant (tocolytic) to halt premature labor. Although initial studies suggested it could be used as a nasal spray and hence would not require hospital admission, it is not used in that form. It was developed by Ferring Pharmaceuticals in Sweden and first reported in the literature in 1985.[1] Originally marketed by Ferring Pharmaceuticals, it is licensed in proprietary and generic forms for the delay of imminent pre-term birth in pregnant adult women.