In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called A Near-Infrared Neutral pH Fluorescent Probe for Monitoring Minor pH Changes: Imaging in Living HepG2 and HL-7702 Cells, published in 2009-03-04, which mentions a compound: 89972-77-0, Name is 4-(p-Tolyl)-2,2:6,2-terpyridine, Molecular C22H17N3, Name: 4-(p-Tolyl)-2,2:6,2-terpyridine.
A near-neutral pH near-IR (NIR) fluorescent probe utilizing a fluorophore-spacer-receptor mol. framework that can modulate the fluorescence emission intensity through a fast photoinduced electron-transfer process was developed. The authors’ strategy was to choose tricarbocyanine (Cy), a NIR fluorescent dye with high extinction coefficients, as a fluorophore, and 4′-(aminomethylphenyl)-2,2′:6′,2”-terpyridine (Tpy) as a receptor. The pH titration indicated that Tpy-Cy can monitor the minor physiol. pH fluctuations with a pKa of ∼7.10 near physiol. pH, which is valuable for intracellular pH researches. The probe responds linearly and rapidly to minor pH fluctuations within the range of 6.70-7.90 and exhibits strong dependence on pH changes. As expected, the real-time imaging of cellular pH and the detection of pH in situ was achieved successfully in living HepG2 and HL-7702 cells by this probe. It is shown that the probe effectively avoids the influence of autofluorescence and native cellular species in biol. systems and meanwhile exhibits high sensitivity, good photostability, and excellent cell membrane permeability.
As far as I know, this compound(89972-77-0)Name: 4-(p-Tolyl)-2,2:6,2-terpyridine can be applied in many ways, which is helpful for the development of experiments. Therefore many people are doing relevant researches.
Reference:
Metal catalyst and ligand design,
Ligand Template Strategies for Catalyst Encapsulation – NCBI