4849. Hydroxyzine

Nomenclature

CAS number: 68-88-2
2-[2-[4-[(4-Chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]ethanol; 1-(p-chloro-α-phenylbenzyl)-4-(2-hydroxyethoxyethyl)piperazine; 1-(p-chlorodiphenylmethyl)-4-[2-(2-hydroxyethoxy)ethyl]piperazine; N-(4-chlorobenzhydryl)-N′-(hydroxyethyloxyethyl)piperazine; 1-(p-chlorobenzhydryl)-4-[2-(2-hydroxyethoxy)ethyl]diethylenediamine; UCB-4492; Tran-Q (Pfizer); Tranquizine.
C21H27ClN2O2; mol wt 374.90.
C 67.28%, H 7.26%, Cl 9.46%, N 7.47%, O 8.54%.

Description and references

H1 receptor antagonist. Outline of commercial prepn: Chem. Week 79 (5), 70 (Aug. 4, 1956); Morren, US 2899436 (1959 to UCB). Pharmacology and metabolism: Cannizaro, Boll. Chim. Farm. 104, 39 (1965); Close et al., Ind. Chim. Belge 33, 94 (1968); eidem, Proc. Eur. Soc. Study Drug Toxic. 9, 144 (1968); S. F. Pong, C. L. Huang, J. Pharm. Sci. 63, 1527 (1974). Pharmacokinetics and antihistaminic activity: F. E. R. Simons et al., J. Allergy Clin. Immunol. 73, 69 (1984); S. Ting et al., ibid. 75, 63 (1985). Clinical trials of efficacy in allergic rhinitis: L. Wong et al., ibid. 67, 223 (1981); in urticaria, R. P. Harvey et al., ibid. 68, 262 (1981); as anti-emetic: R. McKenzie et al., Anesth. Analg. 60, 783 (1981); as pre-surgical sedative: G. Wallace, L. J. Mindlin, ibid. 63, 571 (1984). Toxicity data: E. I. Goldenthal, Toxicol. Appl. Pharmacol. 18, 185 (1971). Comprehensive description: J. Tsau, N. DeAngelis, Anal. Profiles Drug Subs. 7, 319-341 (1978).

Chemical structure

Derivative

Dihydrochloride.

Nomenclature

CAS number: 2192-20-3
Alamon (Grelan); Atarax (Pfizer); Aterax; Durrax (Dermik); Orgatrax (Organon); Quiess (Forest); Vistaril Parenteral (Pfizer).
C21H27ClN2O2.2HCl; mol wt 447.83.
C 56.32%, H 6.53%, Cl 23.75%, N 6.26%, O 7.15%.

Properties

Crystals, mp 193°. Bitter taste. Soly in mg/ml: water <700; chloroform 60; acetone 2; ether <0.1. Solns are unstable to intense uv light. LD50 in rats (mg/kg): 126 i.p.; 950 orally (Goldenthal).

Derivative

Pamoate.

Nomenclature

CAS number: 10246-75-0
Equipose; Masmoran (Pfizer); Paxistil; Vistaril Pamoate (Pfizer).
C21H27ClN2O2.C23H16O6; mol wt 763.27.
C 69.24%, H 5.68%, Cl 4.64%, N 3.67%, O 16.77%.

Properties

Crystals. Practically insol in water.

Therapeutic Category

Anxiolytic. Antihistaminic.

Therapeutic Category (Veterinary)

Has been used as a tranquilizer.

Keywords

Antihistaminic; Piperazines; Anxiolytic