Development of a New Fungicide, Triflumizole

Abstract

Triflumizole [£-4-Chloro-a,a,a-trifluoro-V- (1-imidazol-1 -yl-2 -propoxyethylidene)-o-tolui-dine] is a novel systemic fungicide discovered and developed by Nippon Soda Co., Ltd. We found a new synthetic method of imidazole derivatives and we used this method for the developing of new pesticide. The synthesized imidazole containing compounds, IV-(1-imidazol-l-ylalkoxyalkylidene)anilines showed relatively strong and broad fungicidal activity accompanied with plant growth regulating effect. The highest fungicidal activity was obtained by phenyl substitution with halogen, methyl or trifluoromethyl in the 2-position and halogen in the 4-position, respectively. The introduction of hetero atom, 0, to alkyl chain reduced the effect on plant growth remarkably without reducing fungicidal efficacy. As the results, a compound was selected and is now marketed as a common name triflumizole. Triflumizole showed a wide range of antifungal spectrum in vitro including fungicidal activities to the isolates resistant to benzimidazoles or dicarboximides. In field trials, triflumizole showed a good performance for control of many diseases of crops, including scab, rust and powdery mildew of fruit trees, cereals or vegetables and also seed-born diseases (Gibberella, Cochliobolus, Ustilago, Tilletia and Pyrenophora). The fungicide has both protective and curative efficacies in controlling diseases and also systemic activities in plants. Triflumizole inhibited ergosterol biosynthesis in Ustilago maydis by interfering with demethylation at C-14 of sterol skeleton. Triflumizole was found to have a low toxicity to mammals and fishes and less hazard to the environment. © 1991, Pesticide Science Society of Japan. All rights reserved.