Pimonidazole accumulates in hypoxic cells via covalent binding with macromolecules or by forming reductive metabolites after the reduction of its nitro group.

4'-Hydroxyacetophenone is a potent xanthine oxidase inhibitor.

C004019 is a small molecule PROTAC capable of targeting tau for selective protein degradation from the cell, while recruiting tau and E3 ligase (Vhl) for selective enhancement of tau ubiquitination and proteollyzation. C004019 is a candidate for AD and related tau protein diseases.