Dinuclear Zn complexes with HTQHPN ( N,N,N' ,N'-tetrakis(2-quinolylmethyl)-2-hydroxy-1,3-propanediamine) derivatives have been prepared, and their pyrophosphate (PPi, PO) sensing properties were examined. The ligand library includes six HTQHPN derivatives with electron-donating/withdrawing substituents, an extended aromatic ring, and six-membered chelates upon zinc binding. Complexation of ligand with 2 equiv of Zn promotes small to moderate fluorescence enhancement around 380 nm, but in the cases of HTQHPN, HT(6-FQ)HPN ( N,N,N' ,N'-tetrakis(6-fluoro-2-quinolylmethyl)-2-hydroxy-1,3-propanediamine), and HT(8Q)HPN ( N,N,N' ,N'-tetrakis(8-quinolylmethyl)-2-hydroxy-1,3-propanediamine), subsequent addition of PPi induced a significant fluorescence increase around 450 nm.
View Article and Find Full Text PDFThe tetrakisquinoline ligand HT(6-MeO8Q)HPN (N,N,N',N'-tetrakis(6-methoxy-8-quinolylmethyl)-2-hydroxy-1,3-propanediamine) exhibited Zn-induced fluorescence enhancement with high specificity and sensitivity (I/I = 57 and I/I = 6% in the presence of 2 equiv of Zn; LOD (limit of detection) = 15 nM). This ligand also exhibited fluorescence enhancement specific to inorganic phosphate (PO) in DMF-HEPES buffer (50 mM HEPES, 100 mM KCl, pH = 7.5) (1:1) in the presence of 2 equiv of Zn.
View Article and Find Full Text PDFAn isoquinoline-based ligand, N,N,N',N'-tetrakis(1-isoquinolylmethyl)-2-hydroxy-1,3-propanediamine (1-isoHTQHPN), exhibits a fluorescence increase at 475 nm upon addition of 1 equiv. of Zn(2+) (IZn/I0 = 12, ϕZn = 0.023).
View Article and Find Full Text PDFA convenient synthesis of C3-symmetric tribenzylamine (TBA) derivatives has been investigated. The reaction of benzyl chlorides with acetaldehyde ammonia trimer () in the presence of base afforded tribenzylamines in high yields. This efficient method allows the diverse synthesis of TPA (tris(2-pyridylmethyl)amine) and TQA (tris(2-quinolylmethyl)amine) derivatives.
View Article and Find Full Text PDFDinuclear zinc complex [Zn2(TQHPN)(AcO)](2+) exhibits characteristic fluorescence response (λex = 317 nm and λem = 455 nm) toward pyrophosphate (PPi) with maximum fluorescence upon 1:1 Zn2(TQHPN)-PPi complex formation. The crystallographic investigation utilizing P(1)P(2)-Ph2PPi revealed that the fluorescent response mechanism is due to intramolecular excimer formation of two quinoline rings.
View Article and Find Full Text PDF