Title: Benoxaprofen
CAS Registry Number: 67434-14-4
CAS Name: 2-(4-Chlorophenyl)-a-methyl-5-benzoxazoleacetic acid
Manufacturers' Codes: Compd 90459
Trademarks: Coxigon (Lilly); Opren (Lilly); Oraflex (Lilly)
Molecular Formula: C16H12ClNO3
Molecular Weight: 301.72
Percent Composition: C 63.69%, H 4.01%, Cl 11.75%, N 4.64%, O 15.91%
Literature References: Prepn: D. Evans et al., DE 2324443; eidem, US 3912748 (1973, 1975 both to Lilly); D. W. Dunwell et al., J. Med. Chem. 18, 53 (1975). Analysis by HPLC: S. W. McKay et al., J. Chromatogr. 170, 482 (1979). Pharmacokinetics: D. H. Chatfield et al., Br. J. Clin. Pharmacol. 4, 579 (1977). Metabolism: D. H. Chatfield, J. N. Green, Xenobiotica 8, 133 (1978). Effect on lysosomal enzyme secretion: R. J. Smith, J. Pharmacol. Exp. Ther. 207, 618 (1978). Dissolution and absorption in humans: A. S. Ridolfo et al., J. Pharm. Sci. 68, 850 (1979). Series of clinical studies: Rheumatol. Rehabil. 17, 254-264 (1978). Retrospective study of molecular toxicology: D. F. V. Lewis et al., Toxicology 65, 33 (1990).
Properties: Cream solid from ethanol, mp 189-190°. LD50 orally in mice: 800 mg/kg (Evans, 1973).
Melting point: mp 189-190°
Toxicity data: LD50 orally in mice: 800 mg/kg (Evans, 1973)
Therap-Cat: Anti-inflammatory; analgesic.
Keywords: Analgesic (Non-Narcotic); Anti-inflammatory (Nonsteroidal); Arylpropionic Acid Derivatives.
Status: This monograph has been retired and is no longer subject to revision or update.
Benoxinate Benperidol Benproperine Benserazide Bensuldazic Acid

Benoxaprofen structure.png
Systematic (IUPAC) name
2-[2-(4-chlorophenyl)-1,3-benzoxazol-5-yl]propanoic acid
Clinical data
Legal status  ?
CAS number 67434-14-4 N
ATC code M01AE06
PubChem CID 39941
DrugBank DB04812
ChemSpider 36518 YesY
Chemical data
Formula C16H12ClNO3 
Mol. mass 301.72438 g/mol
 N (what is this?)  (verify)

Benoxaprofen is a chemical compound with the formula C16H12ClNO3. It is a non-steroidal anti-inflammatory drug and was marketed under the brand name Oraflex in the United States and as Opren in Europe by Eli Lilly and Company. Lilly suspended sales of Oraflex in 1982 after reports from the British government and the U.S. Food and Drug Administration (FDA) of adverse effects and deaths linked to the drug.