Design of photoactivatable metallodrugs: Selective and rapid light-induced ligand dissociation from half-sandwich [Ru([9]aneS3)(N–N′)(py)]2+ complexes

Abstract

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Photolabile RuII Half‐Sandwich Complexes Suitable for Developing “Caged” Compounds: Chemical Investigation and Unexpected Dinuclear Species with Bridging Diamine Ligands

“…Selected bond lengths and angles (unexceptional) for both are reported in the Supporting Information (Table S1 and S2, respectively). [22][23][24][25] As an alternative, in this work we also investigated the possibility of introducing the N-N chelate and LЈ on the chlorido-free [Ru( [9]aneS 3 )(dmso) 3 ][CF 3 SO 3 ] 2 (8) intermediate in a two-step reaction (followed by anion metathesis) as described in Scheme 5. [22][23][24][25] As an alternative, in this work we also investigated the possibility of introducing the N-N chelate and LЈ on the chlorido-free [Ru( [9]aneS 3 )(dmso) 3 ][CF 3 SO 3 ] 2 (8) intermediate in a two-step reaction (followed by anion metathesis) as described in Scheme 5.…”

“…[22] Also, monocationic complex 2 shows a broad absorption band at 360 nm that extends into the green region. [22] Also, monocationic complex 2 shows a broad absorption band at 360 nm that extends into the green region.…”

“…In particular, we showed that [Ru( [9]aneS 3 )(bpy)(py)][PF 6 ] 2 and [Ru([9]-aneS 3 )(en)(py)][PF 6 ] 2 (bpy = 2,2Ј-bipyridine, py = pyridine, en = 1,2-diaminoethane) are stable in aqueous solution in the dark but rapidly dissociate the py ligand quantitatively upon irradiation with blue light (for which they have absorption bands). [22] As the organometallic counterparts, the photogenerated aqua species readily formed adducts with 9-EtG and, in the case of [Ru( [9]aneS 3 )(bpy)(OH 2 )] 2+ , with the oligonucleotide d(ATACATGCTACATA).…”

Upconverting Nanoparticles Prompt Remote Near‐Infrared Photoactivation of Ru(II)–Arene Complexes

“…[34] Pyridinato Ru IIarene derivatives display dark-stability and selectively release pyridinato ligands upon visible-light excitation,t hus generating highly reactive aqua species. [35][36][37] Controlling such ar eaction is key for activating the biological activity of Ru II -arene derivatives. 6 ] 2 (2; p-cym = p-cymene, bpy = 2,2'-bipyridine, bpm = 2,2'-bipyrimidine, and m-CCH-Py = 3-ethynylpyridine) and exploited ac lick-chemistry strategy to derivatise the monodentate 3-ethynylpyridine pendant arm with ap hosphonate group, which has high affinity for the UCNP surface.…”

“…2 + ionic species. [35][36][37] Ac ontrol experiment indicates 2 is stable in the dark up to at least 24 hours (see Figure S16 in the Supporting Information). Analogue resultsw ere observedf or 1 and are summarisedi nF igures S17-S19 (see the SupportingI nformation).…”