Recent development of luminescent rhenium(i) tricarbonyl polypyridine complexes as cellular imaging reagents, anticancer drugs, and antibacterial agents

Abstract

There has been fast-growing interest in the exploitation of the photophysical and photochemical properties of luminescent transition metal complexes in biological applications, with a focus on both diagnostic and therapeutic aspects. In particular, the design of luminescent rhenium(i) tricarbonyl polypyridine complexes as cellular imaging reagents and anticancer drugs has received considerable attention for a number of reasons. First, most rhenium(i) tricarbonyl polypyridine complexes possess diverse photophysical and photochemical properties through the coordination of functionalized ligands. The typical photophysical properties of the complexes such as large Stokes shifts, long emission lifetimes, and high photostability allow them to serve as attractive candidates for optical imaging. Also, the cellular uptake of the complexes can be readily quantified by atomic absorption spectroscopy and inductively coupled plasma-mass spectrometry. Additionally, owing to the characteristic infrared absorption bands and the isostructural relationship between rhenium and technetium-99m, rhenium(i) tricarbonyl complexes have been exploited as multimodal imaging reagents for vibrational and radio-imaging, respectively. Furthermore, the facile photosensitizing properties and the three carbon monoxide (CO) ligands render rhenium(i) tricarbonyl complexes promising candidates as photodynamic therapy reagents and photoactivatable CO-releasing molecules, respectively, for cancer treatment. In this Perspective, we describe the recent development of luminescent rhenium(i) tricarbonyl polypyridine complexes as cellular imaging reagents, anticancer drugs, and antibacterial agents.

Properties and prospects for rhenium(i) tricarbonyl N-heterocyclic carbene complexes

“…In the last several years, it has become well established that complexes of rhenium, particularly those bearing a facial tricarbonyl ligand arrangement, possess interesting anticancer properties, and should not be solely relegated to the toolbox of luminescent compounds. 53 Although this article focuses on those rhenium complexes containing NHC ligands, it would be remiss of us when extolling the virtues of this class of compounds, if we did not mention other significant contributions to the field of bioactive rhenium complexes in general. The group of Wilson recently reported the in vitro anticancer activity and in vivo biodistribution studies of a series of rhenium(I) tricarbonyl aqua complexes bearing functionalised bipyridine or phenanthroline ligands ( Figure 12).…”

Linker chemistry dictates the delivery of a phototoxic organometallic rhenium(i) complex to human cervical cancer cells from core crosslinked star polymer nanoparticles

“…Rhenium(I) organometallic compounds show great potential as therapeutic agents, demonstrating cytotoxicity against various cancer cell lines at least equal to cisplatin. [1][2][3][4][5][6][7][8][9][10][11][12] Their photoactive properties can also be exploited as photosensitizers (PS) in photodynamic therapy (PDT), where Re(I) organometallic complexes generate highly reactive oxygen species (ROS), including singlet oxygen ( 1 O 2 ), upon light irradiation. 6,[13][14][15][16][17][18][19][20][21][22] The light-mediated activation of Re(I) organometallic complexes allows spatial and temporal control of activity, and has been demonstrated to have anti-cancer activity by inducing oxidative damage of cellular components leading to cell death.…”

Photophysical and Biological Properties of Iridium Tetrazolato Complexes Functionalised with Fatty Acid Chains

“…Several examples of phosphorescent metal complexes have been used as cellular probes, especially those containing Ru(II), Re(I), Ir(III), Au(I), Pt(II), and lanthanoid cations [7][8][9][10][11][12][13][14]. Chemical design has not only allowed for the fine tuning of the photophysical properties, but it has also conferred organelle targeting, sensing, and even the development of theranostic features.…”

“…t., 1H, H A , splitting = 7.4 Hz), 6.91-6.84 (m, 2H, 2H B ), 6.75 (app. t., 1H, H A , splitting = 7.4 Hz), 6.21 (d, 1H, H B ,J = 7.5 Hz), 6.13 (d, 1H, H B , J = 7.5 Hz), 2.23 (t, 2H, 2H F , J = 7.5 Hz), 1.52-1.45 (m, 2H, 2H F ), 1.22 (broad s, 24H, 24H F ), 0.84 (t, 3H, 3H FMe , J = 7.2 Hz) 13. C NMR (δ/ppm, DMSO-d 6 ): 172.0 (CO), 167.4 (C T ), 167.3 (C T2 ), 163.4 (C A ), 151.6 (C B ), 148.7 (2CH B ), 147.4 (C B ), 144.2 (C B ), 144.0 (C B ), 142.5 (C T5 ), 140.8 (CH T6 ), 138.3 (CH A ), 138.2 (CH A ), 137.9 (C A ), 131.3 (2CH B ), 129.9 (CH B ), 129.1 (CH B ), 128.8 (CH T4 ), 124.8 (CH A ), 124.2 (CH B ), 123.4 (CH A ), 123.3 (CH A ), 121.8 (CH A ), 121.1 (CH B ), 119.6 (CH A ), 119.4 (CH A ), 36.1 (CH F ), 31.1 (CH F ), 28.5 (CH F ), 28.4 (CH F ), 24.7 (CH F ), 22.0 (CH F ),13.9 (CH FMe ).…”