Showing papers by "Shawn C. Burdette published in 2015"
TL;DR: The synthesis and characterization of NTAdeCage is described, the first member in a new class of Zn(2+) photocages that utilizes a light-driven decarboxylation reaction in the metal ion release mechanism and exhibits an almost 6 order of magnitude decrease in metal binding affinity upon uncaging.
Abstract: Metal ion signaling in biology has been studied extensively with ortho-nitrobenzyl photocages; however, the low quantum yields and other optical properties are not ideal for these applications. We describe the synthesis and characterization of NTAdeCage, the first member in a new class of Zn(2+) photocages that utilizes a light-driven decarboxylation reaction in the metal ion release mechanism. NTAdeCage binds Zn(2+) with sub-pM affinity using a modified nitrilotriacetate chelator and exhibits an almost 6 order of magnitude decrease in metal binding affinity upon uncaging. In contrast to other metal ion photocages, NTAdeCage and the corresponding Zn(2+) complex undergo efficient photolysis with quantum yields approaching 30 %. The ability of NTAdeCage to mediate the uptake of (65) Zn(2+) by Xenopus laevis oocytes expressing hZIP4 demonstrates the viability of this photocaging strategy to execute biological assays.
27 citations
TL;DR: Ghosh et al. as discussed by the authors reported that metal binding to the diamine chelator leads to chelation-induced quenching; however, the experimental protocols are incompatible with the aqueous chemistry of FeIII.
Abstract: Recently Ghosh et al. reported on the fluorescent response of commercially available N-(2-aminoethyl)naphthalen-1-amine toward FeII, FeIII, and HgII (K. Ghosh, S. Rathi, P. Gupta, P. Vashisth, V. Pruthi, Eur. J. Inorg. Chem. 2015, 311). The authors conclude that metal binding to the diamine chelator leads to chelation-induced quenching; however, the experimental protocols are incompatible with the aqueous chemistry of FeIII, which precludes this interpretation of the data.
8 citations
TL;DR: The title complex, [Cu(C9H6NO)2(C5H4N)]·H2O, adopts a slightly distorted square-pyramidal geometry in which the axial pyridine ligand exhibits a long Cu—N bond of 2.305 (3) Å.
Abstract: The title complex, [Cu(C9H6NO)2(C5H4N)]·H2O, adopts a slightly distorted square-pyramidal geometry in which the axial pyridine ligand exhibits a long Cu—N bond of 2.305 (3) A. The pyridine ligand forms dihedral angles of 79.5 (5) and 88.0 (1)° with the planes of the two quinolin-2-olate ligands, while the dihedral angle between the quinoline groups of 9.0 (3)° indicates near planarity. The water molecule connects adjacent copper complexes through O—H⋯O hydrogen bonds to phenolate O atoms, forming a network interconnecting all the complexes in the crystal lattice.