5-(3, 3-Dimethyl-l-triazeno) imidazole-4-carboxamide (dicarbazine)(I), synthesized by J. Shealy et al. in 1961 [12], has now found clinical use in the treatment of melanoma. However, the therapeutic effectiveness of the preparation in monochemotherapy, as well as in combination with antitumor agents, is limited by the short lifetime of the enzymatically formed active metabolite 5-(3-methyl-l-triazeno) imidazole-4-carboxamide (II), which is a ...