Synthesis and Biological Activities of Novel Triazole Compounds Containing 1,3-Dioxolane Rings

Author(s): Masahiro Onuma

Many triazole compounds have good fungicidal and plant growth regulating activities. In particular, triazole compounds containing 1,3-dioxolanes have been shown to have remarkable preventative and control activities for a variety of plant diseases. Propiconazole and difenoconazole are two important representatives of this class, especially the latter, which has been used as the most efficient triazole fungicide in the control of some common plant diseases. The key intermediates for its synthesis, however, are not easily obtained, which makes the costs of production and application too high. Following the concept of bioisosterism, we have now synthesized ten novel 1,2,4-triazole compounds containing 1,3-dioxolane rings, 3a~3j, using difenoconazole as the lead compound. In addition, according to empirical data, the presence of an exposed triazole ring is conducive toimprovements of the biological activity. To explore this idea three new compounds 5a~5c containing 1,2,4-triazole-substituted 1,3-dioxolanes were also synthesized.