“Several phenothiazines (methylene blue, azure … B, and quinacrine mustard), polyphenols (myricetin, epicatechin 5-gallate, gossypetin, and 2,3,4,…′,4′-pentahydroxybenzophenone), and the porphyrin ferric dehydroporphyrin IX inhibited tau filament formation with IC50 values in the low micromolar range … assessed by thioflavin S fluorescence, electron microscopy, and Sarkosyl insolubility.”