We report the selective antimetastatic properties of 3(3,3-dimethyl-1-triaz
enyl)-5-methyl-4,5-dihydroisoxazole in the murine transplantable tumor mode
l Lewis lung carcinoma. The compound verifies a previous study on the corre
lation of anti-metastatic, antitumor and cytotoxic properties of aryl- and
heteroaryltriazenes with their Electron Ionization Mass Spectrometry (EI-MS
) behavior The new analog of dacarbazine exhibits a selective antimetastati
c activity accompanied by limited thymus toxicity. The mechanism of action
is unclear nevertheless any antiproliferative or cytotoxic effect is exclud
ed.