Clinical data
Routes of
By mouth
ATC code
  • None
  • 1-[4-[(1-Acetyl-4-piperidinyl)oxy]-2-methoxybenzoyl]-4-(2-oxo-2H-3,1-benzoxazin-1(4H)-yl)piperidine
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass507.587 g·mol−1
3D model (JSmol)
  • O=C1OCc3ccccc3N1C(CC4)CCN4C(=O)c2ccc(cc2OC)OC5CCN(C(C)=O)CC5
  • InChI=1S/C28H33N3O6/c1-19(32)29-15-11-22(12-16-29)37-23-7-8-24(26(17-23)35-2)27(33)30-13-9-21(10-14-30)31-25-6-4-3-5-20(25)18-36-28(31)34/h3-8,17,21-22H,9-16,18H2,1-2H3 ☒N
 ☒NcheckY (what is this?)  (verify)

L-371,257 is a compound used in scientific research which acts as a selective antagonist of the oxytocin receptor with over 800x selectivity over the related vasopressin receptors.[1] It was one of the first non-peptide oxytocin antagonists developed,[2][3][4][5] and has good oral bioavailability, but poor penetration of the blood–brain barrier, which gives it good peripheral selectivity with few central side effects.[6] Potential applications are likely to be in the treatment of premature labour.[7]

See also


  1. ^ Williams PD, Clineschmidt BV, Erb JM, Freidinger RM, Guidotti MT, Lis EV, et al. (November 1995). "1-(1-[4-[(N-acetyl-4-piperidinyl)oxy]-2-methoxybenzoyl]piperidin-4- yl)-4H-3,1-benzoxazin-2(1H)-one (L-371,257): a new, orally bioavailable, non-peptide oxytocin antagonist". Journal of Medicinal Chemistry. 38 (23): 4634–6. doi:10.1021/jm00023a002. PMID 7473590.
  2. ^ Bell IM, Erb JM, Freidinger RM, Gallicchio SN, Guare JP, Guidotti MT, et al. (June 1998). "Development of orally active oxytocin antagonists: studies on 1-(1-[4-[1-(2-methyl-1-oxidopyridin-3-ylmethyl)piperidin-4-yloxy]-2- methoxybenzoyl]piperidin-4-yl)-1,4-dihydrobenz[d][1,3]oxazin-2-one (L-372,662) and related pyridines". Journal of Medicinal Chemistry. 41 (12): 2146–63. doi:10.1021/jm9800797. PMID 9622556.
  3. ^ Kuo MS, Bock MG, Freidinger RM, Guidotti MT, Lis EV, Pawluczyk JM, et al. (November 1998). "Nonpeptide oxytocin antagonists: potent, orally bioavailable analogs of L-371,257 containing a 1-R-(pyridyl)ethyl ether terminus". Bioorganic & Medicinal Chemistry Letters. 8 (21): 3081–6. doi:10.1016/S0960-894X(98)00568-X. PMID 9873680.
  4. ^ Williams PD, Bock MG, Evans BE, Freidinger RM, Gallicchio SN, Guidotti MT, et al. (May 1999). "Nonpeptide oxytocin antagonists: analogs of L-371,257 with improved potency". Bioorganic & Medicinal Chemistry Letters. 9 (9): 1311–6. doi:10.1016/S0960-894X(99)00181-X. PMID 10340620.
  5. ^ Wyatt PG, Allen MJ, Chilcott J, Foster A, Livermore DG, Mordaunt JE, et al. (May 2002). "Identification of potent and selective oxytocin antagonists. Part 1: indole and benzofuran derivatives". Bioorganic & Medicinal Chemistry Letters. 12 (10): 1399–404. doi:10.1016/S0960-894X(02)00159-2. PMID 11992786.
  6. ^ Ring RH, Malberg JE, Potestio L, Ping J, Boikess S, Luo B, et al. (April 2006). "Anxiolytic-like activity of oxytocin in male mice: behavioral and autonomic evidence, therapeutic implications". Psychopharmacology. 185 (2): 218–25. doi:10.1007/s00213-005-0293-z. PMID 16418825. S2CID 13647805.
  7. ^ Hawtin SR, Ha SN, Pettibone DJ, Wheatley M (January 2005). "A Gly/Ala switch contributes to high affinity binding of benzoxazinone-based non-peptide oxytocin receptor antagonists". FEBS Letters. 579 (2): 349–56. doi:10.1016/j.febslet.2004.10.108. PMID 15642343. S2CID 38088139.