Amine arms, appending

The bis(2-picolyl)amine (Dpa) unit designed for zinc complexation has also been incorporated into various receptors for pyrophosphate sensing and detection. Smith and coworkers studied a series of dinuclear zinc receptors (34, 35, and 36) and found that receptor 35 shows high selectivity and affinity for pyrophosphate under physiological conditions. " Other receptors with only one appended Dpa arm (34) or jiara-substituted Dpa arms (36) show no binding toward pyrophosphate. The binding constant for this receptor with pyrophosphate and phosphate was determined to be 1.52 X 10 and 7.3 x 10 M , respectively. A fluorescent IDA was developed for pyrophosphate using a coumarin-derived indicator 37. A more recent study... 

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