Myclobutanil-d9

Myclobutanil-d₉ is intended for use as an internal standard for the quantification of myclobutanil by GC- or LC-MS. Myclobutanil is a triazole fungicide.¹ It is active against the plant pathogenic fungus U. avenae (ED₅₀ = 45 mg/ml) that is sensitive to the triazole fungicide triadimefon but not four triadimefon-resistant strains (ED₅₀s = >1,000 mg/ml). Myclobutanil (2.52 and 45 µg/ml, respectively) reduces the number and severity of powdery mildew colonies on apple seedling leaves in greenhouse and field studies.² It reduces body weight and male breeding performance, as well as increases offspring deaths, liver and testis weight, anogenital distance, and serum testosterone levels, in male offspring when administered to pregnant rat dams at a dose of 2,000 ppm.³ Formulations containing myclobutanil have been used as fungicides against plant pathogenic fungi in residential, aquatic, and agricultural settings.