A novel compound, trivially named visoltricin, has been isolated from cultures of Fusarium tricinctum on corn. Its structure has been established by chemical reactions and spectroscopic methods (UV, IR, MS, ¹H NMR, and ¹³C NMR) as 3-[1-methyl-4-(3-methyl-2-butenyl)imidazol-5-yl]-2-propenoic acid methyl ester (molecular formula C₁₃H₁₈N₂O₂ molecular weight 234.297). It is the first imidazole derivative produced by a Fusarium species. About 30% of the tested isolates (33) of F. tricinctum from various substrates and geographic areas produced visoltricin when grown on corn. None of the 14 isolates tested from the United States produced the compound. Visoltricin was toxic to Artemia salina larvae (LD₅₀ = 8.5 × 10⁻⁷M) and cytotoxic (IG₅₀ < 10⁻⁵ M) to 6 human tumor cell lines (of 60 lines tested). Visoltricin induced on rabbit eye an interesting miotic effect which has been correlated to the anticholinesterase activity shown by the compound against human serum and pure enzymes.