Synthesis and Properties of the Antileukemic Agent 5(or 4)-[3,3-Bis(2-chloroethyl)-1-triazeno]imidazole-4(or 5)-carboxamide

The antileukemic agent 5(or 4)-[3,3-bis(2-chloroethyl)-1-triazeno]imidazole-4 (or 5)-carboxamide (II, NSC-82196) is an unstable compound that is easily convertible to an isomeric transformation product. By taking appropriate precautions, however, the triazene may be prepared in good yield, with very little of the transformation product as contaminant, and may be stored for long periods at low temperatures. The quality of specimens of II may be estimated from its infrared spectrum and that of its transformation product.