Clinical trials with 1,3-bis(2-chloroethyl)-1-nitrosourea, NSC-409962.

nitrosourea (BCNTJ) is shown in Chart 1. The back ground for the development of the nitrosoureas has been recently reviewed by Schabel et al. (4). Initial interest in the group of compounds of which BCNU is a member was stimulated by the finding of the Cancer Chemotherapy National Service Center screening program that i-methyl i-nitroso-3-nitroguanidine (NSC-9369) had weak activity against i.p. implanted Li210 leukemia. The chloroethyl and bromoethyl-substituted analogs of NSC-9369, synthe sized by Baker et al. (5), showed the most consistent ac tivity. Because of their structural relation to the nitroso guanidines, a series of nitrosoureas were synthesized and tested. The first derivative screened, i-methyl-i-ni