Fenarimol, sold under the tradenames Bloc, Rimidin and Rubigan, is a fungicide which acts against rusts, blackspot and mildew fungi. It is used on ornamental plants, trees, lawns, tomatoes, peppers, eggplants, cucumbers and melons. It is mainly used to control powdery mildew. It works by inhibiting the fungus's biosynthesis of important steroid molecules (via blockade of the CYP51 enzyme).
^Reynolds, Todd B.; Lim, Wilson; Melse, Youri; Konings, Mickey; Phat Duong, Hung; Eadie, Kimberly; Laleu, Benoît; Perry, Benjamin; Todd, Matthew H.; Ioset, Jean-Robert; van de Sande, Wendy W. J. (2018). "Addressing the most neglected diseases through an open research model: The discovery of fenarimols as novel drug candidates for eumycetoma". PLOS Neglected Tropical Diseases. 12 (4): e0006437. doi:10.1371/journal.pntd.0006437. ISSN1935-2735.
Fenarimol in the Pesticide Properties DataBase (PPDB)