The synthesis of three spin labeled derivatives of N-[N'-(2-chloroethy
l)-N'-nitrosocarbamoyl] amino acids is reported, The new nitrosoureas
are obtained by condensation of the corresponding N-[N'-(2-chloroethyl
)-N'-nitrosocarbamoyl] amino acid with 2,2,6,6-tetramethyl-1-oxyl-4-am
inopiperidine using dicyclohexylcarbodiimide. Their chemical structure
s are confirmed by elemental analysis, IR, MS, and EPR spectroscopy, A
ll newly synthesized compounds showed high antitumour activity against
the lymphoid leukemia L1210 in BDF1 mice.