Synthesis and Primary Screening for Growth Inhibitors of L1210 Cells of Cholesteryl p-[3-(2-chloroethyl)-3-nitrosoureido] Phenylthioacetate

Cholesteryl p-[3-(2-chloroethyl_-3-nitrosoureido] phenylthioaccetate (2) was synthesized : an intermediate, p-[3(2-chloroethyl_-3-nitrosoureido] phenylthioacetic acid (1) is a congener of an antitumor chlorambucil which both the -CH$_{2}$CH$_{2}$-linkage and -N(CH$_{2}$CH$_{2}$Cl)$_{2}$ group of chlorambucil molecule is doubly modified into the respective -S-linkage and -NH-CO-NNO-CH$_{2}$CH$_{2}$CL group. The attackment of cholesterol moiety as a carrier group to p-[3-(2-chloroethyl-3nitrosoureido] phenylthioacetic acid was accomplished through the esterification of cholesterol with p-[3-(2-chloroethyl-3-nitrosoureido] phenylthioacetyl chloride which was obtained from the treatment of p-[3-(2-chloroethyl)-3-nitrosourei-do] phenylthioaceticacid with SOCL$_{2}$, p-[3-(2-chloroethyl)ureido]]-phenythioacetic acid was nitrosated with NaNO$_{2}$ IN 98-100% HCOOH to give exclusively p-[3-(2-chloroethyl_-3-nitrosoureido] phenylthioacetic acid. Antitumor evaluation of compounds, 1 and 2 on L 1210 leukemia did show significant activity (ED$_{40}$ : 1.14.mu./ml and 8.4.mu.g/ml, repectively). Further studies were subjected..