Fusidic Acid

Title: Fusidic Acid
CAS Registry Number: 6990-06-3
CAS Name: (3a,4a,8a,9b,11a,13a,14b,16b,17Z)-16-(Acetyloxy)-3,11-dihydroxy-29-nordammara-17(20),24-dien-21-oic acid
Additional Names: 3a,11a,16b-trihydroxy-29-nor-8a,9b,13a,14b-dammara-17(20),24-dien-21-oic acid 16-acetate; 3a,11a,16b-trihydroxy-4a,8,14-trimethyl-18-nor-5a,8a,9b,13a,14b-cholesta-17(20),24-dien-21-oic acid 16-acetate; 3,11,16-trihydroxy-4,8,10,14-tetramethyl-17-(1¢-carboxyisohept-4¢-enylidene)cyclopentanoperhydrophenanthrene 16-acetate; ramycin
Trademarks: Fucithalmic (Leo Pharm)
Molecular Formula: C31H48O6
Molecular Weight: 516.71
Percent Composition: C 72.06%, H 9.36%, O 18.58%
Literature References: Antibiotic isolated from the fermentation broth of Fusidium coccineum; structurally similar to cephalosporin P1, q.v. Inhibits bacterial protein synthesis by interference with elongation factor G. Isoln and structure: W. O. Godtfredsen et al., Nature 193, 987 (1962); Lancet I, 928 (1962); W. O. Godtfredsen, S. Vangedal, Tetrahedron 18, 1029 (1962). Identity with ramycin: H. Vanderhaeghe et al., Nature 205, 710 (1965). Structure: D. Arigoni et al., Experientia 19, 521 (1963). Stereochemistry: W. O. Godtfredsen et al., Tetrahedron 21, 3505 (1965). Synthetic studies: W. G. Dauben et al., J. Am. Chem. Soc. 94, 8593 (1972); R. E. Ireland, U. Hengartner, ibid. 3652; M. Tanabe et al., Tetrahedron Lett. 1977, 1481. Total synthesis: W. G. Dauben et al., J. Am. Chem. Soc. 104, 303 (1982). Review of structure-activity relationships: W. von Daehne et al., Adv. Appl. Microbiol. 25, 95-146 (1979). Series of articles on pharmacology and clinical experience: Int. J. Antimicrob. Ag. 12, Suppl. 2, S1-S93 (1999). Review of use in Staphylococcus aureus infections: D. Dobie, J. Gray, Arch. Dis. Child. 89, 74-77 (2004).
Properties: Crystals from ether or benzene, mp 192-193°. [a]D20 -9° (chloroform). uv max: 204 nm (e 9900). pK: 5.35 in water. Sol in alc, acetone, chloroform, pyridine, dioxane; sparingly sol in water, ether, hexane. LD50 in mice (g/kg): 1.2 s.c.; 1.5 orally (Godtfredsen).
Melting point: mp 192-193°
pKa: pK: 5.35 in water
Optical Rotation: [a]D20 -9° (chloroform)
Absorption maximum: uv max: 204 nm (e 9900)
Toxicity data: LD50 in mice (g/kg): 1.2 s.c.; 1.5 orally (Godtfredsen)
Derivative Type: Sodium salt
CAS Registry Number: 751-94-0
Additional Names: Sodium fusidate
Manufacturers' Codes: ZN-6
Trademarks: Fucidin (Leo Pharm); Fucidine (Leo Pharm)
Molecular Formula: C31H47NaO6
Molecular Weight: 538.69
Percent Composition: C 69.12%, H 8.79%, Na 4.27%, O 17.82%
Properties: Crystals, sol in water. LD50 in mice (g/kg): 0.2 i.v. (Godtfredsen, Nature 1962).
Toxicity data: LD50 in mice (g/kg): 0.2 i.v. (Godtfredsen, Nature 1962)
Therap-Cat: Antibacterial.
Therap-Cat-Vet: Antibacterial.
Keywords: Antibacterial (Antibiotics).
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Fusidic acid
Systematic (IUPAC) name
2-[(1S,2S,5R,6S,7S,10S,11S,13S,14Z,15R,17R)-13-(acetyloxy)-5,17-dihydroxy-2,6,10,11-tetramethyltetracyclo[,7.011,15]heptadecan-14-ylidene]-6-methylhept-5-enoic acid
Clinical data
Trade names Fucidin, Fucithalmic
AHFS/Drugs.com Micromedex Detailed Consumer Information
Legal status  ?
Pharmacokinetic data
Bioavailability 91% oral bioavailability
Protein binding 97 to 99%
Half-life Approximately 5 to 6 hours in adults
CAS number 6990-06-3 YesY
ATC code D06AX01 D09AA02 (dressing) J01XC01 S01AA13
PubChem CID 3000226
DrugBank DB02703
ChemSpider 2271900 YesY
UNII 59XE10C19C YesY
KEGG D04281 N
ChEBI CHEBI:29013 YesY
Synonyms Sodium fusidate
Chemical data
Formula C31H48O6 
Mol. mass 516.709
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Fusidic acid is a bacteriostatic antibiotic that is often used topically in creams and eyedrops, but may also be given systemically as tablets or injections. The global problem of advancing antimicrobial resistance has led to a renewed interest in its use recently.[1]