Title: Aspirin
CAS Registry Number: 50-78-2
CAS Name: 2-(Acetyloxy)benzoic acid
Synonyms: salicylic acid acetate; 2-acetoxybenzoic acid; acetylsalicylic acid
Trademarks: Acylpyrin (Slovakofarma); Angettes (BMS); Asatard (Boehringer, Ing.); Aspro (Roche); Cardioaspirin (Bayer); Cardiprin (Reckitt Benckiser); Cemirit (Bayer); Claragine (Nicholas); Ecotrin (GSK); Empirin (GSK); Encaprin (Procter & Gamble); Rhonal (Aventis); Solprin (Reckitt Benckiser)
Molecular Formula: C9H8O4
Molecular Weight: 180.16
Percent Composition: C 60.00%, H 4.48%, O 35.52%
Literature References: Prepn: C. Gerhardt,
Ann. 87, 149 (1853). Manuf from salicylic acid and acetic anhydride:
Faith, Keyes & Clark's Industrial Chemicals, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York, 4th ed., 1975) pp 117-120. Crystallization from acetone: Hamer, Phillips,
US 2890240 (1959 to Monsanto). Novel process involving distillation: Edmunds,
US 3235583 (1966 to Norwich Pharm.). Crystal structure: P. J. Wheatley,
J. Chem. Soc. (Suppl.) 1964, 6036. Characterization of a second polymorphic form: P. Vishweshwar
et al., J. Am. Chem. Soc. 127, 16802 (2005). Toxicity data: E. R. Hart,
J. Pharmacol. Exp. Ther. 89, 205 (1947). Evaluation as a risk factor in Reye's syndrome: P. J. Waldman
et al., J. Am. Med. Assoc. 247, 3089 (1982). Review of clinical trials in prevention of myocardial infarction and stroke: P. C. Elwood,
Drugs 28, 1-5 (1984). Symposium on aspirin therapy:
Am. J. Med. 74, no. 6A, 1-109 (1983). Clinical trials in prevention of colorectal cancer: R. S. Sandler
et al., N. Engl. J. Med. 348, 883 (2003); J. A. Baron
et al., ibid. 891. Comprehensive description: K. Florey,
Anal. Profiles Drug Subs. 8, 1-46 (1979). Monograph: M. J. H. Smith, P. K. Smith,
The Salicylates (Interscience, New York, 1966) 313 pp. Book:
Acetylsalicylic Acid, H. J. M. Barnett
et al., Eds. (Raven, New York, 1982) 278 pp.
Properties: Monoclinic tablets or needle-like crystals. d 1.40. mp 135° (rapid heating); the melt solidifies at 118°. uv max (0.1
N H2SO4): 229 nm (E1%1cm 484); (CHCl3): 277 nm (E1%1cm 68). Is odorless, but in moist air it is gradually hydrolyzed into salicylic and acetic acids and acquires the odor of acetic acid. Stable in dry air. pK (25°) 3.49. One gram dissolves in 300 ml water at 25°, in 100 ml water at 37°, in 5 ml alcohol, 17 ml chloroform, 10-15 ml ether. Less soluble in anhydr ether. Decomp by boiling water or when dissolved in solns of alkali hydroxides and carbonates. Inorganic salts of acetylsalicylic acid are soluble in water (esp the Ca salt,
q.v.), but are decomposed quickly. LD50 orally in mice, rats: 1.1, 1.5 g/kg (Hart).
Melting point: mp 135° (rapid heating)
pKa: pK (25°) 3.49
Absorption maximum: uv max (0.1
N H2SO4): 229 nm (E1%1cm 484); (CHCl3): 277 nm (E1%1cm 68)
Density: d 1.40
Toxicity data: LD50 orally in mice, rats: 1.1, 1.5 g/kg (Hart)
Derivative Type: Guaiacol ester
CAS Registry Number: 55482-89-8
Synonyms: Guacetisal
Trademarks: Guaiaspir (Lampugnani)
Molecular Formula: C16H14O5
Molecular Weight: 286.28
Percent Composition: C 67.13%, H 4.93%, O 27.94%
Derivative Type: Methyl ester
see Methyl Acetylsalicylate
Derivative Type: Phenyl ester
see Phenyl Acetylsalicylate
CAUTION: Potential symptoms of overexposure are increased blood clotting time; nausea, vomiting; liver, kidney injury. Direct contact may cause eye, skin and upper respiratory irritation.
See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 6.
Therap-Cat: Analgesic; antipyretic; anti-inflammatory; antithrombotic.
Therap-Cat-Vet: Analgesic; antipyretic; anti-inflammatory; antithrombotic.
Keywords: Analgesic (Non-Narcotic); Anti-inflammatory (Nonsteroidal); Salicylic Acid Derivatives; Antipyretic; Antithrombotic.
