ATP-responsive Mn(II)-based contrast agent for MRI.

A novel diacetylpyridylcarbohydrazide-DAPyCOHz-based manganese(II) chelate with dipicolylamine/zinc(II) (DPA/Zn) arms (MnLDPA-Zn2) was developed for adenosine triphosphate (ATP) responsive magnetic resonance imaging (MRI) contrast applications. Compound 2 shows enhanced relaxivity ( = 11.52 mM s) upon selective ATP binding over other phosphates.