Title: Phentolamine
CAS Registry Number: 50-60-2
CAS Name: 3-[[(4,5-Dihydro-1
H-imidazol-2-yl)methyl](4-methylphenyl)amino]phenol
Synonyms: 2-[
N-(
m-hydroxyphenyl)-
p-toluidinomethyl]imidazoline; 2-(
m-hydroxy-
N-p-tolylanilinomethyl)-2-imidazoline; 2-(
N¢-p-tolyl-
N¢-m-hydroxyphenylaminomethyl)-2-imidazoline
Manufacturers' Codes: C-7337
Molecular Formula: C17H19N3O
Molecular Weight: 281.35
Percent Composition: C 72.57%, H 6.81%, N 14.94%, O 5.69%
Literature References: a-Adrenergic blocker. Prepn: K. Miescher
et al., US 2503059 (1950 to Ciba); E. Urech
et al., Helv. Chim. Acta 33, 1386 (1950). Pharmacology and toxicity: R. Meier
et al., Proc. Soc. Exp. Biol. Med. 71, 70 (1949). HPLC determn in biological samples: B. D. Kerger
et al., Anal. Biochem. 170, 145 (1988). Diagnostic use: G. Spergel
et al., J. Am. Med. Assoc. 211, 266 (1970). Review of pharmacology and therapeutic applications: L. Gould, C. V. R. Reddy,
Am. Heart J. 92, 397-402 (1976). Clinical efficacy of combination with papaverine in impotence: A. Bechara
et al., J. Urol. 157, 2132 (1997).
Properties: Crystals, mp 174-175°.
Melting point: mp 174-175°
Derivative Type: Hydrochloride
CAS Registry Number: 73-05-2
Molecular Formula: C17H19N3O.HCl
Molecular Weight: 317.81
Percent Composition: C 64.25%, H 6.34%, N 13.22%, O 5.03%, Cl 11.16%
Properties: Bitter crystals, mp 239-240°. One gram dissolves in 50 ml water, in 70 ml alcohol. Very slightly sol in chloroform. Practically insol in acetone, ethyl acetate. pH of 1% aq soln 4.5-5.5. Aq solns cannot be stored. LD50 in rats (mg/kg): 75 i.v.; 275 s.c.; 1250 orally (Meier).
Melting point: mp 239-240°
Toxicity data: LD50 in rats (mg/kg): 75 i.v.; 275 s.c.; 1250 orally (Meier)
Derivative Type: Methanesulfonate
CAS Registry Number: 65-28-1
Synonyms: Phentolamine mesylate
Trademarks: Regitine (Novartis); Rogitine (Novartis)
Molecular Formula: C17H19N3O.CH3SO3H
Molecular Weight: 377.46
Percent Composition: C 57.28%, H 6.14%, N 11.13%, O 16.95%, S 8.49%
Properties: Crystals, mp 177-181°. One gram dissolves in 50 ml water, 23 ml alcohol, 660 ml chloroform. pH of 1% aq soln 4.5-5.5. Aq solns cannot be stored.
Melting point: mp 177-181°
Therap-Cat: Antihypertensive in treatment of pheochromocytoma; diagnostic aid (pheochromocytoma). In treatment of male erectile dysfunction.
Keywords: Antihypertensive; Imidazole Derivatives; Antipheochromocytoma; Diagnostic Aid.