ABSTRACT
The chemotherapeutic activity of 12 newly synthesized nitrosoureas was compared in tests using Yoshida sarcoma ascites cells implanted into the wall of the descending colon in Sprague-Dawley rats. Cyclophosphamide and the nitrosoureas BCNU, MeCCNU, and chlorozotocin served as positive controls. Among the nitrosoureas tested, 1-(2-hydroxyethyl)-3-(2-chloroethyl)-3-nitrosourea (hydroxyethyl-CNU), chlorozotocin, 1-(2-chloroethyl)-1-nitroso-3-(4-morpholino) urea, 1-(2-chloroethyl)-1-nitroso-3-(1-piperidino) urea, 4-[1-(2-chloroethyl)-1-nitroso-3-[4-(2,6-dimethylmorpholino)] urea, and 1-(2-chloroethyl)-1-nitroso-3-(3,4-methylenedioxybenzyl) urea were found to be the most active compounds in this tumor model. Based on the present results, morpholino-CNU is considered the most promising compound among these newly synthesized BCNU analogues.