Protective Effect of S, -Aminoethylisothiuronium* Br* HBr and Related Compounds Against X-Radiation Death in Mice.

Abstract

Twelve compounds of the general type R(CH2)xSR[image] were tested for radiation protective activity in mice. Two new protective agents, S,beta-aminoethylisothiuronium.Br. HBr and S,gamma-aminopropylisothiuronium.Br.HBr have greater chemical stability than beta-mercaptoethylamine and provide a wider margin between the effective dose in mice and the dose required to produce acute toxic effects. The isothiuronium derivatives provided better protection in the 3 strains of mice tested than did beta-mercaptoethylamine. A free amino group beta or gamma to a sulfhydryl or isothiuronium group appears to be essential for maximum protective activity in compounds of this type.