Title: Phenytoin
CAS Registry Number: 57-41-0
CAS Name: 5,5-Diphenyl-2,4-imidazolidinedione
Additional Names: diphenylhydantoin
Trademarks: Di-Hydan (Genopharm); Dilantin (Pfizer); Hydantin (Orion); Hydantol (Fujinaga); Lehydan (Abigo); Zentropil (Novartis)
Molecular Formula: C15H12N2O2
Molecular Weight: 252.27
Percent Composition: C 71.42%, H 4.79%, N 11.10%, O 12.68%
Literature References: Prepn from benzophenone: H. R. Henze, US 2409754 (1946 to Parke, Davis); of sodium salt from benzil, urea and NaOH: Biltz, Ber. 41, 1391 (1908); 44, 411 (1911). Pharmacology: Gillis et al., J. Pharmacol. Exp. Ther. 179, 599 (1971). Toxicity of base: G. Stille, I. Brunckow, Arzneim.-Forsch. 4, 723 (1954); of sodium salt: G. B. Fink, E. A. Swinyard, J. Pharmacol. Exp. Ther. 127, 318 (1959). Reviews: Damato, Prog. Cardiovasc. Dis. 12, 1-15 (1969); Dreifus, Watanabe, Am. Heart J. 80, 709-713 (1970). Review of carcinogenicity studies: IARC Monographs 13, 201-225 (1977). Comprehensive description: J. Philip et al., Anal. Profiles Drug Subs. 13, 417-445 (1984).
Properties: Powder, mp 295-298°. Practically insol in water. One gram dissolves in about 60 ml alcohol, about 30 ml acetone. Sol in alkali hydroxides. LD50 in mice (mg/kg): 92 i.v.; 110 s.c. (Stille, Brunckow).
Melting point: mp 295-298°
Toxicity data: LD50 in mice (mg/kg): 92 i.v.; 110 s.c. (Stille, Brunckow)
Derivative Type: Sodium salt
CAS Registry Number: 630-93-3
Additional Names: Phenytoin soluble; sodium 5,5-diphenyl hydantoinate
Trademarks: Aurantin (Pfizer); Dintoina (Recordati); Epanutin (Pfizer); Phenhydan (Desitin); Pyoredol (Aventis); Tacosal (Stada)
Molecular Formula: C15H11N2NaO2
Molecular Weight: 274.25
Percent Composition: C 65.69%, H 4.04%, N 10.21%, Na 8.38%, O 11.67%
Properties: White powder; bitter, soapy taste. Somewhat hygroscopic. Easily dissociated even by weak acids (incl CO2 absorbed on exposure to air) regenerating phenytoin. One gram dissolves in 10.5 ml alc; in ~66 ml water (aq soln turbid unless pH adjusted to >11.7, the pH of a satd soln). Insol in ether, chloroform. LD50 orally in mice: 490 mg/kg (Fink, Swinyard).
Toxicity data: LD50 orally in mice: 490 mg/kg (Fink, Swinyard)
CAUTION: Phenytoin is reasonably anticipated to be a human carcinogen: Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-216.
Therap-Cat: Anticonvulsant; antiepileptic.
Therap-Cat-Vet: Anticonvulsant.
Keywords: Anticonvulsant. |