Title: Ambrisentan
CAS Registry Number: 177036-94-1
CAS Name: (aS)-a-[(4,6-Dimethyl-2-pyrimidinyl)oxy]-b-methoxy-b-phenylbenzenepropanoic acid
Manufacturers' Codes: BSF-208075; LU-208075
Molecular Formula: C22H22N2O4
Molecular Weight: 378.42
Percent Composition: C 69.83%, H 5.86%, N 7.40%, O 16.91%
Literature References: Nonpeptide endothelin ETA receptor antagonist. Prepn: H. Riechers et al., WO 9611914; eidem, US 5932730 (1996, 1998 both to BASF); H. Riechers et al., J. Med. Chem. 39, 2123 (1996). Pharmacology: H. Vatter et al., Clin. Neuropharmacol. 26, 73 (2003). Clinical evaluation in pulmonary arterial hypertension: N. Galié et al., J. Am. Coll. Cardiol. 46, 529 (2005). Review of development and therapeutic potential: G. E. Billman, Curr. Opin. Invest. Drugs 3, 1483-1486 (2002).
Derivative Type: (±)-Form
CAS Registry Number: 713516-99-5
Properties: Crystals from diethylether, mp 190-191°.
Melting point: mp 190-191°
Therap-Cat: Antihypertensive.
Keywords: Antihypertensive; Endothelin Receptor Antagonist.
Ambrosin Ambroxol Ambucaine Ambucetamide Ambuphylline

Ambrisentan structure.svg
Systematic (IUPAC) name
(2S)-2-[(4,6-dimethylpyrimidin-2-yl)oxy]-3-methoxy- 3,3-diphenylpropanoic acid
Clinical data
AHFS/ monograph
Licence data EMA:Link, US FDA:link
Pregnancy cat. X (AU) X (US)
Legal status Prescription Only (S4) (AU) -only (CA) POM (UK) -only (US)
Routes Oral
Pharmacokinetic data
Bioavailability Undetermined
Protein binding 99%
Half-life 15 hours (terminal)
CAS number 177036-94-1 YesY
ATC code C02KX02
PubChem CID 6918493
ChemSpider 5293690 YesY
Chemical data
Formula C22H22N2O4 
Mol. mass 378.421 g/mol
 YesY (what is this?)  (verify)

Ambrisentan (U.S. trade name Letairis; E.U. trade name Volibris; India trade name pulmonext by MSN labs ) is a drug indicated for use in the treatment of pulmonary hypertension.

It functions as an endothelin receptor antagonist, and is selective for the type A endothelin receptor (ETA).[1] Once daily oral ambrisentan 2.5 to 10 mg/day significantly improved exercise capacity (6-minute walk distance) compared with placebo in two double-blind, multicenter trials (ARIES-1 & ARIES-2).[2]

Ambrisentan was approved for sale by the U.S. Food and Drug Administration (FDA) on June 15, 2007 for the once-daily treatment of pulmonary arterial hypertension.[3][4][5] It was later approved by the European Medicines Agency for use in the EU on April 2008.[6] Ambrisentan had previously been designated an orphan drug by both the FDA and the European Commission, in August 2004 and May 2005 respectively.[7]