Title: Clarithromycin
CAS Registry Number: 81103-11-9
CAS Name: 6-O-Methylerythromycin
Manufacturers' Codes: A-56268; TE-031
Trademarks: Biaxin (Abbott); Clarosip (Grenthal); Clathromycin (Taisho); Cyllind (Abbott); Klacid (Abbott); Klaricid (Abbott); Macladin (Guidotti); Naxy (Sanofi Winthrop); Veclam (Zambon); Zeclar (Abbott)
Molecular Formula: C38H69NO13
Molecular Weight: 747.95
Percent Composition: C 61.02%, H 9.30%, N 1.87%, O 27.81%
Literature References: Semisynthetic macrolide antibiotic; derivative of erythromycin, q.v. Prepn: Y. Watanabe et al., EP 41355; eidem, US 4331803 (1981, 1982 both to Taisho); and in vitro antibacterial activity: S. Morimoto et al., J. Antibiot. 37, 187 (1984). In vitro and in vivo antibacterial activity: P. B. Fernandes et al., Antimicrob. Agents Chemother. 30, 865 (1986). Comparative antibacterial spectrum in vitro: C. Benson et al., Eur. J. Clin. Microbiol. 6, 173 (1987); H. M. Wexler, S. M. Finegold, ibid. 492. HPLC determn in biological fluids: D. Croteau et al., J. Chromatogr. 419, 205 (1987); in plasma: H. Amini, A. Ahmadiani, J. Chromatogr. B 817, 193 (2005). Acute toxicity study: S. Abe et al., Chemotherapy (Tokyo) 36, Suppl. 3, 274 (1988). Symposium on pharmacology and comparative clinical studies: J. Antimicrob. Chemother. 27, Suppl. A, 1-124 (1991). Comprehensive description: I. I. Salem, Anal. Profiles Drug Subs. Excip. 24, 45-85, (1996).
Properties: Colorless needles from chloroform + diisopropyl ether (1:2), mp 217-220° (dec). Also reported as crystals from ethanol, mp 222-225° (Morimoto). uv max (CHCl3): 288 nm (e 27.9). uv max (CHCl3): 240, 288 nm; (methanol): 211, 288 nm. [a]D24 -90.4° (c = 1 in CHCl3). Stable at acidic pH. LD50 in male, female mice, male, female rats (mg/kg): 2740, 2700, 3470, 2700 orally, 1030, 850, 669, 753 i.p., >5000 all s.c. (Abe).
Melting point: mp 217-220° (dec); mp 222-225° (Morimoto)
Optical Rotation: [a]D24 -90.4° (c = 1 in CHCl3)
Absorption maximum: uv max (CHCl3): 288 nm (e 27.9). uv max (CHCl3): 240, 288 nm
Toxicity data: LD50 in male, female mice, male, female rats (mg/kg): 2740, 2700, 3470, 2700 orally, 1030, 850, 669, 753 i.p., >5000 all s.c. (Abe)
Therap-Cat: Antibacterial.
Keywords: Antibacterial (Antibiotics); Macrolides.
Clathrates Clavulanic Acid Clazosentan Clazuril Clebopride

Clarithromycin structure.svg
Clarithromycin ball-and-stick.png
Systematic (IUPAC) name
(3R,4S,5S,6R,7R,9R,11S,12R,13S,14S)-6-{[(2S,3R,4S,6R) -4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy} -14-ethyl-12,13-dihydroxy-4-{[(2R,4S,5S,6S)-5-hydroxy -4-methoxy-4,6-dimethyloxan-2-yl]oxy}-7 -methoxy-3,5,7,9,11,13-hexamethyl -1-oxacyclotetradecane-2,10-dione
Clinical data
Trade names Biaxin
AHFS/ monograph
MedlinePlus a692005
Pregnancy cat. C (USA)
B3 (Aus)
Legal status prescription only
Routes oral, intravenous
Pharmacokinetic data
Bioavailability 50%
Protein binding low binding
Metabolism hepatic
Half-life 3-4 h
CAS number 81103-11-9 YesY
ATC code J01FA09
PubChem CID 5284534
DrugBank DB01211
ChemSpider 21112273 N
KEGG D00276 YesY
Chemical data
Formula C38H69NO13 
Mol. mass 747.953 g/mol
 N (what is this?)  (verify)

Clarithromycin (6-O-methyl erythromycin) is a macrolide antibiotic used to treat pharyngitis, tonsillitis, acute maxillary sinusitis, acute bacterial exacerbation of chronic bronchitis, pneumonia (especially atypical pneumonias associated with Chlamydophila pneumoniae), skin and skin structure infections. In addition, it is sometimes used to treat legionellosis, Helicobacter pylori, and lyme disease. Recently there has been research towards whether Clarithromycin can be used to effectively treat idiopathic hypersomnia.[1]

Clarithromycin is available under several brand names, for example Binoclar, Bioclar, Truclar, Crixan, Claritt, Clarac, Biaxin, Klaricid, Klacid, Klaram, Klabax, Claripen, Clarem, Claridar, Fromilid, Clacid, Clacee, Vikrol, Infex, Clariwin, Resclar, Ranbaxy and Clarihexal,Clarinova 250mg & 500mg, Monoclar (by Bosnalijek)...