TY  - JOUR
A1  - Kole, Goutam Kumar
A1  - Košćak, Marta
A1  - Amar, Anissa
A1  - Majhen, Dragomira
A1  - Božinović, Ksenija
A1  - Brkljaca, Zlatko
A1  - Ferger, Matthias
A1  - Michail, Evripidis
A1  - Lorenzen, Sabine
A1  - Friedrich, Alexandra
A1  - Krummenacher, Ivo
A1  - Moos, Michael
A1  - Braunschweig, Holger
A1  - Boucekkine, Abdou
A1  - Lambert, Christoph
A1  - Halet, Jean‐François
A1  - Piantanida, Ivo
A1  - Müller‐Buschbaum, Klaus
A1  - Marder, Todd B.
T1  - Methyl Viologens of Bis‐(4’‐Pyridylethynyl)Arenes – Structures, Photophysical and Electrochemical Studies, and their Potential Application in Biology
JF  - Chemistry – A European Journal
N2  - A series of bis‐(4’‐pyridylethynyl)arenes (arene=benzene, tetrafluorobenzene, and anthracene) were synthesized and their bis‐N‐methylpyridinium compounds were investigated as a class of π‐extended methyl viologens. Their structures were determined by single crystal X‐ray diffraction, and their photophysical and electrochemical properties (cyclic voltammetry), as well as their interactions with DNA/RNA were investigated. The dications showed bathochromic shifts in emission compared to the neutral compounds. The neutral compounds showed very small Stokes shifts, which are a little larger for the dications. All of the compounds showed very short fluorescence lifetimes (<4 ns). The neutral compound with an anthracene core has a quantum yield of almost unity. With stronger acceptors, the analogous bis‐N‐methylpyridinium compound showed a larger two‐photon absorption cross‐section than its neutral precursor. All of the dicationic compounds interact with DNA/RNA; while the compounds with benzene and tetrafluorobenzene cores bind in the grooves, the one with an anthracene core intercalates as a consequence of its large, condensed aromatic linker moiety, and it aggregates within the polynucleotide when in excess over DNA/RNA. Moreover, all cationic compounds showed highly specific CD spectra upon binding to ds‐DNA/RNA, attributed to the rare case of forcing the planar, achiral molecule into a chiral rotamer, and negligible toxicity toward human cell lines at ≤10 μM concentrations. The anthracene‐analogue exhibited intracellular accumulation within lysosomes, preventing its interaction with cellular DNA/RNA. However, cytotoxicity was evident at 1 μM concentration upon exposure to light, due to singlet oxygen generation within cells. These multi‐faceted features, in combination with its two‐photon absorption properties, suggest it to be a promising lead compound for development of novel light‐activated theranostic agents.
KW  - cell imaging
KW  - DNA/RNA binding
KW  - methyl viologen
KW  - singlet oxygen
KW  - two-photon absorption
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-287126
VL  - 28
IS  - 40
ER  -