Title: Fludrocortisone
CAS Registry Number: 127-31-1
CAS Name: (11b)-9-Fluoro-11,17,21-trihydroxypregn-4-ene-3,20-dione
Additional Names: 9a-fluorohydrocortisone; 9a-fluoro-17-hydroxycorticosterone; 9a-fluorocortisol; fluodrocortisone; fluohydrisone; fluohydrocortisone
Trademarks: Astonin H (Merck KGaA)
Molecular Formula: C21H29FO5
Molecular Weight: 380.45
Percent Composition: C 66.30%, H 7.68%, F 4.99%, O 21.03%
Literature References: Prepn: J. Fried, E. F. Sabo, J. Am. Chem. Soc. 76, 1455 (1954); GB 792224; J. Fried, US 2852511 (both 1958 to Olin Mathieson). Series of articles on pharmacology and metabolism: Arzneim.-Forsch. 21, 1103-1158 (1971). Comprehensive description of the acetate: K. Florey, Anal. Profiles Drug Subs. 3 281-306 (1974).
Properties: Crystals, dec 260-262°. [a]D23 +139° (c = 0.55 in 95% ethanol). uv max (ethanol): 239 nm (e 17600). Soly in water: 0.14 mg/ml.
Optical Rotation: [a]D23 +139° (c = 0.55 in 95% ethanol)
Absorption maximum: uv max (ethanol): 239 nm (e 17600)
Derivative Type: 21-Acetate
CAS Registry Number: 514-36-3
Trademarks: Florinef (BMS)
Molecular Formula: C23H31FO6
Molecular Weight: 422.49
Percent Composition: C 65.39%, H 7.40%, F 4.50%, O 22.72%
Properties: Crystals, polymorphic, mp 233-234° (occasionally mp 205-208°, resolidifying on further heating, then mp 226-228°). Crystallizing procedure: R. P. Graber, C. S. Snoddy, US 2957013 (1960 to Merck & Co.). [a]D23 +123° (c = 0.64 in chloroform). uv max (ethanol): 238 nm (e 16800). Soly (mg/ml): water 0.04; acetone 56; alc 20; chloroform 20; ether 4.
Melting point: Crystals, polymorphic, mp 233-234° (occasionally mp 205-208°, resolidifying on further heating, then mp 226-228°)
Optical Rotation: [a]D23 +123° (c = 0.64 in chloroform)
Absorption maximum: uv max (ethanol): 238 nm (e 16800)
Therap-Cat: Mineralocorticoid.
Therap-Cat-Vet: Mineralocorticoid.
Keywords: Mineralocorticoid.
Flufenacet Flufenamic Acid Flufenoxuron Fluindione Flumazenil

Fludrocortisone structure.png
Systematic (IUPAC) name
9-fluoro-11,17-dihydroxy-17- (2-hydroxyacetyl)- 10,13-dimethyl- 1,2,6,7,8,9,10,11,12, 13,14,15,16,17- tetradecahydrocyclopenta[a]phenanthren-3-one
Clinical data
AHFS/Drugs.com monograph
Pregnancy cat. C
Legal status  ?
Routes Oral
Pharmacokinetic data
Protein binding High
Metabolism Hepatic
Half-life 3.5 hours
CAS number 127-31-1 YesY
ATC code H02AA02
PubChem CID 31378
IUPHAR ligand 2873
DrugBank DB00687
ChemSpider 29111 YesY
UNII U0476M545B YesY
KEGG D07967 YesY
ChEBI CHEBI:50885 YesY
Chemical data
Formula C21H29FO5 
Mol. mass 380.45 g/mol
 N (what is this?)  (verify)

Fludrocortisone (also called 9α-fluorocortisol or 9α-fluorohydrocortisone) is a synthetic corticosteroid with moderate glucocorticoid potency and much greater mineralocorticoid potency. The brand name in the U.S. and Canada is Florinef.