The invention relates to compounds having Formula 1: A-L-B Formula 1or pharmaceutically acceptable salts thereof, wherein: A is a dicarbonyl sequestering moiety comprising a substituted aryl group or a substituted heteroaryl group； L is an optional linker moiety； and B is a mitochondrial targeting moiety. The invention also relates to pharmaceutical compositions containing such compounds and salts, and to the use of such compounds and salts for treating diabetes, preferably hyperglycaemic diabetes. A mass spectrometry probe and to a method of labelling a biological molecule for mass spectrometry detection are also described.
