ABSTRACT
The fluorescent chelator (FC-1) was designed by combining a metal-chelating unit and a ThT-based Aß aggregate-binding fluorescent unit. FC-1 is a cell membrane-penetrable chelator with a moderate chelation ability to Cu(2+) and Zn(2+) and can target metal-Aß40 aggregates. Treatment with FC-1 led to enhanced cytotoxicity of the aggregates, because the aggregates were converted into a pool of oligomers.
Subject(s)
Amyloid beta-Peptides/chemistry , Chelating Agents/chemistry , Metals/chemistry , Peptide Fragments/chemistry , Amyloid beta-Peptides/metabolism , Coordination Complexes/chemistry , Coordination Complexes/toxicity , Copper/chemistry , HeLa Cells , Humans , Hydrogen-Ion Concentration , Molecular Conformation , Peptide Fragments/metabolism , Zinc/chemistryABSTRACT
Two polymorphs of biphenyl-4,4'-diaminium bis(3-carboxy-4-hydroxybenzenesulfonate) dihydrate, C(12)H(14)N(2)(2+)·2C(7)H(5)O(6)S(-)·2H(2)O, have been obtained and crystallographically characterized. Polymorph (I) crystallizes in the space group P2(1)/c with Z' = 2 and polymorph (II) in the space group P-1 with Z' = 0.5. The benzidinium cation in (II) is located on a crystallographic inversion centre. In both (I) and (II), the sulfonic acid H atoms are transferred to the benzidine N atoms, forming dihydrated 1:2 molecular adducts (base-acid). In the crystal packings of (I) and (II), the component ions are linked into three-dimensional networks by combinations of X-H...O (X = O, N and C) hydrogen bonds. In addition, π-π interactions are observed in (I) between inversion-related benzene rings [centroid-centroid distances = 3.632â (2) and 3.627â (2)â Å]. In order to simplify the complex three-dimensional networks in (I) and (II), we also give their rationalized topological analyses.
