Imazalil-d5 (sulfate)

Imazalil-d₅ (sulfate) is intended for use as an internal standard for the quantification of imazalil by GC- or LC-MS. Imazalil is an imidazole fungicide that inhibits ergosterol biosynthesis.¹ Imazalil inhibits the growth of various fungi in vitro including P. italicum, A. niger, U. maydis, B. alii, and C. cucumerinum in a pH-dependent manner (MICs = 0.005-2 μg/ml at pH 7).² It inhibits S. cerevisiae, but not rat liver microsomal, cytochrome P450 enzymes (CYPs; IC₅₀s = 0.088 and 80 μM, respectively), as well as aromatase CYP19 from human placental microsomes (IC₅₀ = 0.34 μM).^1,3 Imazalil activates the murine pregnane X receptor (PXR) in a concentration-dependent manner in a cell-based reporter assay.⁴ It increases hepatic CYP3A11 and CYP2B10 mRNA levels in mice when administered at a dose of 100 mg/kg. Imazalil also increases Ki-67-positive nuclei in liver sections and hepatic MCM2 mRNA levels, markers of cell proliferation, in mice when co-administered with the murine constitutive androstane receptor (mCAR) agonist TCPOBOP . Formulations containing imazalil have been used to control fungal infection in agriculture.