Expanding the palette of phenanthridinium cations.

TitleExpanding the palette of phenanthridinium cations.
Publication TypeJournal Article
Year of Publication2014
AuthorsCairns, AG, Senn, HMartin, Murphy, MP, Hartley, RC
JournalChemistry
Volume20
Issue13
Pagination3742-51
Date Published2014 Mar 24
ISSN1521-3765
KeywordsCations, Computer Simulation, Cyclization, DNA, Fluorescent Dyes, Intercalating Agents, Models, Chemical, Molecular Structure, Phenanthridines
Abstract

5,6-Disubstituted phenanthridinium cations have a range of redox, fluorescence and biological properties. Some properties rely on phenanthridiniums intercalating into DNA, but the use of these cations as exomarkers for the reactive oxygen species (ROS), superoxide, and as inhibitors of acetylcholine esterase (AChE) do not require intercalation. A versatile modular synthesis of 5,6-disubstituted phenanthridiniums that introduces diversity by Suzuki–Miyaura coupling, imine formation and microwave-assisted cyclisation is presented. Computational modelling at the density functional theory (DFT) level reveals that the novel displacement of the aryl halide by an acyclic N-alkylimine proceeds by an S(N)Ar mechanism rather than electrocyclisation. It is found that the displacement of halide is concerted and there is no stable Meisenheimer intermediate, provided the calculations consistently use a polarisable solvent model and a diffuse basis set.

DOI10.1002/chem.201304241
Alternate JournalChemistry
Citation Key10.1002/chem.201304241
PubMed ID24677631
PubMed Central IDPMC4164275
Grant ListMC_U105663142 / / Medical Research Council / United Kingdom
BB/D526310/1 / / Biotechnology and Biological Sciences Research Council / United Kingdom
BB/I012826/1 / / Biotechnology and Biological Sciences Research Council / United Kingdom