Title: Oxyphenbutazone
CAS Registry Number: 129-20-4
CAS Name: 4-Butyl-1-(4-hydroxyphenyl)-2-phenyl-3,5-pyrazolidinedione
Additional Names: 4-butyl-2-(p-hydroxyphenyl)-1-phenyl-3,5-pyrazolidinedione; 1-phenyl-2-(p-hydroxyphenyl)-3,5-dioxo-4-n-butylpyrazolidine; 1-(p-hydroxyphenyl)-2-phenyl-4-butylpyrazolidine-3,5-dione; p-hydroxyphenylbutazone
Manufacturers' Codes: G-27202
Trademarks: Californit (Merckle); Crovaril; Flogitolo; Flogoril; Frabel; Neo-Farmadol; Oxalid (USV); Rapostan (Mepha); Tandearil (Novartis); Visubutina
Molecular Formula: C19H20N2O3
Molecular Weight: 324.37
Percent Composition: C 70.35%, H 6.21%, N 8.64%, O 14.80%
Literature References: Prepn: Hafliger, US 2745783 (1956 to Geigy); Pfister, Hafliger, Helv. Chim. Acta 40, 395 (1957).
Derivative Type: Monohydrate
CAS Registry Number: 7081-38-1
Trademarks: Imbun (Merckle); Phlogistol (Spitzner); Phlogase (Adenylchemie); Phlogont (Azupharma)
Properties: Crystals, mp 96°. Anhydr crystals from ether + petr ether, mp 124-125°. Acidic reaction. Soluble in ethanol, methanol, chloroform, benzene, ether. Forms a water-soluble sodium salt.
Melting point: mp 96°; mp 124-125°
Therap-Cat: Anti-inflammatory.
Keywords: Anti-inflammatory (Nonsteroidal); Pyrazolones.
Oxyphencyclimine Oxyphenisatin Acetate Oxyphenonium Bromide Oxypinocamphone Oxytetracycline

Systematic (IUPAC) name
Clinical data
AHFS/Drugs.com International Drug Names
Legal status  ?
CAS number 129-20-4 YesY
ATC code M01AA03 M02AA04 S01BC02
PubChem CID 104811
DrugBank DB03585
ChemSpider 94610 YesY
UNII A7D84513GV YesY
KEGG D08324 YesY
Chemical data
Formula C19H20N2O3 
Mol. mass 324.379 g/mol
 N (what is this?)  (verify)

Oxyphenbutazone is a non-steroidal anti-inflammatory drug (NSAID).[1] It is a metabolite of phenylbutazone.[2]