Title: Hydroxychloroquine
CAS Registry Number: 118-42-3
CAS Name: 2-[[4-[(7-Chloro-4-quinolinyl)amino]pentyl]ethylamino]ethanol
Additional Names: 7-chloro-4-[4-[ethyl(2-hydroxyethyl)amino]-1-methylbutylamino]quinoline; 7-chloro-4-[4-(N-ethyl-N-b-hydroxyethylamino)-1-methylbutylamino]quinoline; 7-chloro-4-[5-(N-ethyl-N-2-hydroxyethylamino)-2-pentyl]aminoquinoline; oxychloroquine; oxichlorochine
Molecular Formula: C18H26ClN3O
Molecular Weight: 335.87
Percent Composition: C 64.37%, H 7.80%, Cl 10.56%, N 12.51%, O 4.76%
Literature References: Prepd by reacting a mixture of 4,7-dichloroquinoline, phenol and N¢-ethyl-N¢-b-hydroxyethyl-1,4-pentadiamine at 125-130°: Surrey, Hammer, J. Am. Chem. Soc. 72, 1814 (1950); Surrey, US 2546658 (1951 to Sterling Drug). Use in combination with cyclophosphamide and azathioprine, q.q.v. in the treatment of rheumatoid arthritis: D. J. McCarty, G. F. Carrera, J. Am. Med. Assoc. 248, 1718 (1982). Reassessment in the treatment of rheumatoid arthritis: Am. J. Med. 75, no. 1A, 1-56 (1983). Series of articles on clinical use: ibid. 85, Suppl. 4A, 1-71 (1988).
Properties: Crystals from ethylene dichloride and Skellysolve B; mp 89-91°.
Melting point: mp 89-91°
Derivative Type: Diphosphate
Molecular Formula: C18H26ClN3O.2H3PO4
Molecular Weight: 531.86
Percent Composition: C 40.65%, H 6.06%, Cl 6.67%, N 7.90%, O 27.07%, P 11.65%
Properties: Recrystallized from ethanol, mp 168-170° (dec).
Melting point: mp 168-170° (dec)
Derivative Type: Sulfate
CAS Registry Number: 747-36-4
Trademarks: Ercoquin; Plaquenil Sulfate (Winthrop); Quensyl
Molecular Formula: C18H26ClN3O.H2SO4
Molecular Weight: 433.95
Percent Composition: C 49.82%, H 6.50%, Cl 8.17%, N 9.68%, O 18.43%, S 7.39%
Properties: White crystalline powder; odorless but has a bitter taste. pH of aq solns about 4.5. Exists in two forms, the usual form mp ~240°, the other mp ~198°. Freely sol in water. Practically insol in alcohol, chloroform, ether.
Melting point: mp ~240°; mp ~198°
Therap-Cat: Antimalarial; antirheumatic; lupus erythematosus suppressant.
Keywords: Antimalarial; Antiarthritic/Antirheumatic; Lupus Erythematosus Suppressant.
Hydroxycodeinone Hydroxydione Sodium Hydroxyglutamic Acid Hydroxylamine Hydroxylupanine

Hydroxychloroquine ball-and-stick animation.gif
Systematic (IUPAC) name
Clinical data
Trade names Plaquenil
AHFS/Drugs.com monograph
MedlinePlus a601240
Pregnancy cat. D (Au), C (U.S.)
Legal status POM (UK), ℞-only (U.S.)
Routes Oral
Pharmacokinetic data
Half-life 1–2 months
Excretion Renal
CAS number 118-42-3 YesY
ATC code P01BA02
PubChem CID 3652
DrugBank DB01611
ChemSpider 3526 YesY
KEGG D08050 YesY
Chemical data
Formula C18H26ClN3O 
Mol. mass 335.872 g/mol
 N (what is this?)  (verify)

Hydroxychloroquine is an antimalarial drug, sold under the trade names Plaquenil, Axemal (in India), Dolquine and Quensyl, also used to reduce inflammation in the treatment of rheumatoid arthritis (see disease-modifying antirheumatic drugs) and lupus. Hydroxychloroquine differs from chloroquine by the presence of a hydroxyl group at the end of the side chain: The N-ethyl substituent is beta-hydroxylated. It is available for oral administration as hydroxychloroquine sulfate (plaquenil) of which 200 mg contains 155 mg base in chiral form. Hydroxychloroquine has similar pharmacokinetics to chloroquine, with quick gastrointestinal absorption and is eliminated by the kidney. Cytochrome P450 enzymes (CYP 2D6, 2C8, 3A4 and 3A5) N-desethylated Hydroxychloroquine to Ndesethylhydroxychloroquine.[1]