The Effects of Substituted Benzimidazoles on the Growth of Viruses and the Nucleic Acid Metabolism of Host Cells

Summary The antiviral effects of three substituted benzimidazoles, 4,5,6,trichloro- l-β-D-ribofuranosyl benzimidazole, 2-mercapto-1 -(β-4-pyridethyl) benzimidazole and 2-(α-hydroxybenzyl) benzimidazone, have been investigated and compared with their effects on the RNA metabolism of the host cells. 4,5,6,trichloro-l-β-D-ribofuranosyl benzimidazole and 2-mercapto-l-(β-4- pyridethyl) benzimidazole inhibit the growth of influenza A and parainfluenza 1 in calf kidney cells, and vaccinia in L cells, but they also reduce the synthesis of cellular RNA proportionately. They inhibit the growth of EMC in L cells, but only at concentrations at which host cell RNA synthesis is very much reduced. Their action is therefore not specific to a virus induced process. In contrast, 2-(α-hydroxybenzyl) benzimidazole suppresses the growth of encephalomyocarditis virus in L cells at concentrations which have little effect on host cell RNA synthesis.