Novel asymmetrically functionalized bis-dipicolylamine metal complexes: peripheral decoration of a potent anion recognition scaffold.

We report the design and synthesis of a novel class of asymmetrically functionalized, ditopic bis-dipicolylamine (BDPA) ligands. A key feature of this research involved the controlled, sequential functional group decoration of a potent molecular recognition scaffold. Calorimetric screening identified a BDPA analogue as a highly potent (K(a) approximately 10(6) M(-1)) and selective sensor for inorganic phosphate.