Title: Chlortetracycline
CAS Registry Number: 57-62-5
CAS Name: [4S-(4a,4aa,5aa,6b,12aa)]-7-Chloro-4-dimethylamino-1,4,4a,5,5a,6,11,12a-octahydro-3,6,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-2-naphthacenecarboxamide
Additional Names: 7-chlorotetracycline
Trademarks: Acronize (Am. Cyanamid); Aureocina; Aureomycin (Lederle); Biomitsin; Centraureo (Central); Chrysomykine; Orospray (Voquinol)
Molecular Formula: C22H23ClN2O8
Molecular Weight: 478.88
Percent Composition: C 55.18%, H 4.84%, Cl 7.40%, N 5.85%, O 26.73%
Literature References: Antibiotic substance isolated from the substrate of Streptomyces aureofaciens: Duggan, Ann. N.Y. Acad. Sci. 51, 177 (1948); US 2482055 (1949 to Am. Cyanamid); Broschard et al., Science 109, 199 (1949). Structure: Stephens et al., J. Am. Chem. Soc. 74, 4976 (1952); 76, 3568 (1954). Crystal structure: Donohue et al., ibid. 85, 851 (1963). Absolute configuration: Dobrynin et al., Tetrahedron Lett. 1962, 901. Purification: Winterbottom et al., US 2899422 (1959 to Am. Cyanamid). Improved process: Miller et al.; Goodman, US 2987449; US 3050446 (1961, 1962 to Am. Cyanamid). Toxicity: E. I. Goldenthal, Toxicol. Appl. Pharmacol. 18, 185 (1971). Comprehensive description: G. Schwartzman et al., Anal. Profiles Drug Subs. 8, 101-137 (1979).
Properties: Golden-yellow crystals, mp 168-169°. [a]D23 -275.0° (methanol). uv max (0.1N HCl): 230, 262.5, 367.5 nm; (0.1N NaOH): 255, 285, 345 nm. Soly in water: 0.5-0.6 mg/ml. Very sol in aq solns above pH 8.5. Freely sol in the Cellosolves, dioxane, and Carbitol. Slightly sol in methanol, ethanol, butanol, acetone, ethyl acetate, benzene. Practically insol in ether, petr ether.
Melting point: mp 168-169°
Optical Rotation: [a]D23 -275.0° (methanol)
Absorption maximum: uv max (0.1N HCl): 230, 262.5, 367.5 nm; (0.1N NaOH): 255, 285, 345 nm
Derivative Type: Crystal salt
Properties: White powder. Insol in water. Marketed as suspension preserved with methyl and propyl p-hydroxybenzoate; stable and fully active for at least one year at room temps.
Derivative Type: Hydrochloride
CAS Registry Number: 64-72-2
Trademarks: Aureociclina; Isphamycin
Molecular Formula: C22H23ClN2O8.HCl
Molecular Weight: 515.34
Percent Composition: C 51.27%, H 4.69%, Cl 13.76%, N 5.44%, O 24.84%
Properties: Bitter, yellow rhomboid crystals. Dec above 210°. [a]D23 -240°. Soly at about 28° (mg/ml): water 8.6; methanol 17.4; ethanol 1.7: Weiss et al., Antibiot. Chemother. 7, 374 (1957). Sol in solns of alkali hydroxides and carbonates. Practically insol in acetone, ether, chloroform, dioxane. pH of satd aq soln 2.8-2.9. LD50 orally in rats: 10300 mg/kg (Goldenthal).
Optical Rotation: [a]D23 -240°
Toxicity data: LD50 orally in rats: 10300 mg/kg (Goldenthal)
Therap-Cat: Antibacterial; antiamebic.
Therap-Cat-Vet: Antimicrobial.
Keywords: Antiamebic; Antibacterial (Antibiotics); Tetracyclines.
Chlorthalidone Chlorthenoxazin(e) Chlorthion? Chlorzoxazone Cholane

Systematic (IUPAC) name
Clinical data
AHFS/ Micromedex Detailed Consumer Information
Legal status  ?
Routes Oral, IV, topical
Pharmacokinetic data
Bioavailability 30%
Protein binding 50 to 55%
Metabolism Hepatic (75%)
Half-life 5.6 to 9 hours
Excretion Renal and biliary
CAS number 57-62-5 YesY
ATC code A01AB21 D06AA02 J01AA03 S01AA02 QG51AA08 QJ51AA03
ChemSpider 10469370 YesY
KEGG D07689 YesY
Chemical data
Formula C22H23ClN2O8 
Mol. mass 478.88 g/mol
 N (what is this?)  (verify)

Chlortetracycline (trade name Aureomycin, Lederle) is a tetracycline antibiotic, the first tetracycline to be identified. It was discovered in 1945 by Benjamin Minge Duggar working at Lederle Laboratories under the supervision of Yellapragada Subbarow. Duggar identified the antibiotic as the product of an actinomycete he cultured from a soil sample collected from Sanborn Field at the University of Missouri.[1] The organism was named Streptomyces aureofaciens and the isolated drug, Aureomycin, because of their golden color.

In veterinary medicine, chlortetracycline is commonly used to treat conjunctivitis in cats.[2]