N-[4-(5,6-Dimethoxy-N-phthalimidinyl)phenyl]maleimide is a thiol-reactive compound. N-[4-(5,6-Dimethoxy-N-phthalimidinyl)phenyl]maleimide selectively reacts with thiols. It can be used as a pre-column labeling reagent in HPLC and in the determination of thiols in biological fluids.
