7035. Parbendazole

Nomenclature

CAS number: 14255-87-9
(5-Butyl-1H-benzimidazol-2-yl)carbamic acid methyl ester; methyl 5-butyl-2-benzimidazolecarbamate; 5-butyl-2-(carbomethoxyamino)benzimidazole; SKF-29044; Helmatac (SK & F); Verminum (Squibb); Worm Guard (SK & F).
C13H17N3O2; mol wt 247.29.
C 63.14%, H 6.93%, N 16.99%, O 12.94%.

Description and references

Prepd from 4-butyl-o-phenylenediamine and carbomethoxycyanamide: Actor et al., Nature 215, 321 (1967); GB 1123317 and Stedman; Actor, Pagano, US 3480642; US 3574845 (1968, 1969, 1971 all to SKF). Activity: Ostmann, Scheidy, Prog. Antimicrob. Anticancer Chemother., Proc. 6th Int. Congr. Chemother. 1, 159 (1970). Identification of metabolites: Dunn et al., J. Med. Chem. 16, 996 (1973).

Chemical structure

Properties

Crystals from aq ethanol, mp 225-227° (dec). uv max (95% ethanol/1N HCl): 282, 288 nm (ε 16200, 20000). Practically insol in water. LD50 in mice, rats (g/kg): >4 orally, both species (Actor).

Therapeutic Category (Veterinary)

Anthelmintic.