[Kinetic study of the effect of N-nitroso-N-alkylurea on the development of leukemia L1210].

A comparative kinetic study of antitumor activity of seven alkyl derivatives of nitrosourea in the process of ascites leucosis L 1210 was undertaken. The efficacy was estimated on the basis of determining the coefficient of inhibition chi and the increase of an average survival of treated mice. The tumor was found to be mostly sensitive to nitroso derivatives containing chloroethyl groups--1,3-bis (2-chloroethyl)-1-nitrosourea, 1-(2-chloroethyl)-(3-cyclohexil)-1-nitrosourea, 1-(2-chloroethyl)-3-(4-methylcyclohexil)-1-nitrosourea. 1-nitroso-1-methylbiuret and 1-nitroso-1-methylurea proved to be highly effective too, while 1,3-dimethyl-1-nitrosourea and 1,3-diethyl-1-nitrosourea were found to be insignificantly effective.