Effect of the length of polyoxyethylene substituents on luminescent bimetallic lanthanide bioprobes

Acridone‐Benzimidazole Ring‐Fused Ligands: A New Class of Sensitizers of Lanthanide Luminescence via Low‐Energy Excitation

“…which therefore provides a tighter binding to the smallest lanthanide ions; this assumption is supported by a previous study involving L1 which demonstrated that such a ligand preferentially binds the larger lanthanide ions over the smaller ones; [42] in addition the weakly electron-donating [38,43] no single crystals suitable for Xray analysis could be grown, most probably in view of the presence of the three fluxional pendants so that this assumption could not be proven. 1 [44] which generate up to 24 resonances in the aromatic region (that is three times more than the eight non-equivalent aromatic protons of the ligands).…”

Application of Metal Coordination Chemistry To Explore and Manipulate Cell Biology

“…For this reason, the 4-pyridyl substituted helicates are more promising for in vivo application 390. The low cytotoxicity of the helicates is demonstrated by HeLa cells being unaffected when treated with up to 500 μM for 24 h 389. Bright Eu(III) emission can be seen in cells after incubation with concentrations above 10 μM in as little as 15 min.…”

“…Bright Eu(III) emission can be seen in cells after incubation with concentrations above 10 μM in as little as 15 min. Localization in vesicles indicates uptake via a lysosomally directed and/or recycling endosomal pathway 389. One drawback of these helicates is their short excitation wavelength (330–365 nm), although they are photoluminescent with two-photon excitation 374…”

Synthesis and spectroscopy of anionic tridentate benzimidazole-pyridine carboxylate and tetrazolate chromophore ligands

“…Chart 1 shows the three known reference ligands HR1-HR3 [23,29]. New 2,4,6-trisubstituted pyridine P2 was obtained by monooxidation of bis-methanol 3 (itself prepared from chelidamic acid in three multi-gram steps by modified literature procedures [5][6][7][30][31][32]) with SeO 2 in dioxane (Scheme 3) [12]. Until now, only one report described an analogue of P2 as a by-product of bis-oxidation of a substituted bis-methanol-pyridine by SeO 2 [33].…”

“…Polydentate carboxylate [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] and tetrazolate [21][22][23][24] ligands are strong chelators for lanthanide ions and efficient sensitizers of their luminescence. Here, we report on synthesis and spectroscopy of anionic tridentate carboxylate and tetrazolate benzimidazole-pyridine ligands HL1-HL7 that are functionalized with chromophore and solubilizing groups (Schemes 1 and 2).…”