Title:  Tetracaine Hydrochloride 
CAS Registry Number:  136-47-0 
CAS Name:  4-(Butylamino)benzoic acid 2-(dimethylamino)ethyl ester monohydrochloride 
Additional Names:  p-butylaminobenzoyl-2-dimethylaminoethanol hydrochloride;  2-dimethylaminoethyl 4-n-butylaminobenzoate hydrochloride;  dicain;  amethocaine hydrochloride 
Trademarks:  Anethaine (Glaxo);  Decicain (Winthrop);  Pantocaine (Hoechst);  Pontocaine Hydrochloride (Sanofi Winthrop);  Tonexol (Pharmaton) 
Molecular Formula:  C15H25ClN2O2 
Molecular Weight:  300.82 
Percent Composition:  C 59.89%, H 8.38%, Cl 11.79%, N 9.31%, O 10.64% 
Literature References:  Prepn:  US 1889645 (1932); GB 815144 (1959 to Abbott).  Prepn of pharmaceutical dosage forms:  Shupe, US 3272700 (1966 to Sterling Drug).  Mechanism of action studies:  Y.-W. Leung et al., J. Infect. Dis. 136, 679 (1977).  Toxicity study:  Dawes, Br. J. Pharmacol. Chemother. 1, 90 (1946).  Acute toxicity:  B. A. Bopp et al., J. Pharm. Sci. 67, 882 (1978).  Comprehensive description:  M. Riaz, Anal. Profiles Drug Subs. 18, 379-411 (1989). 
Properties:  Faintly bitter crystals producing transient numbness of the tongue.  mp 147-150°.  pKa 8.39.  uv max (water):  225, 310 nm (e 14108, 26352); (0.1N H2SO4):  229, 281, 312 nm (E1%1cm 509, 55, 76); (methanol):  226, 310 nm (e 7586, 29512); (chloroform):  308 nm (e 27542).  Sol at 20° in 7.5 parts water, 40 parts alcohol; 30 parts chloroform.  Practically insol in ether, benzene, acetone.  The aq soln is neutral to litmus.  Aq solns are stable and may be sterilized by brief boiling.  LD50 i.p. in mice:  70 mg/kg (Dawes); also reported as LD50 in female mice (mg/kg):  13 i.v.; 35 s.c. (Bopp). 
Melting point:  mp 147-150° 
pKa:  pKa 8.39 
Absorption maximum:  uv max (water):  225, 310 nm (e 14108, 26352); (0.1N H2SO4):  229, 281, 312 nm (E1%1cm 509, 55, 76); (methanol):  226, 310 nm (e 7586, 29512); (chloroform):  308 nm (e 27542) 
Toxicity data:  LD50 i.p. in mice:  70 mg/kg (Dawes); also reported as LD50 in female mice (mg/kg):  13 i.v.; 35 s.c. (Bopp) 
Therap-Cat:  Anesthetic (local). 
Therap-Cat-Vet:  Anesthetic (topical). 
Keywords:  Anesthetic (Local).   |