Luminescent cyclometalated platinum compounds with N, P, and O^O ligands: Density-functional theory studies and analysis of the anticancer potential

Luminescent platinum cyclometalated complexes are species of interest mainly due to their applications in the optoelectronic and biological fields, especially with regard to their anticancer activity. Given this level of interest, a series of cyclometalated (2-[2′-thienyl]pyridinate, thpy and 2-[2,4...

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Detalles Bibliográficos
Autores: Leal Cruz, Jorge, Durá Gracia, Gema, Jalon Sotes, Félix Ángel, Zafon, Elisenda, Massaguer, Anna, Cuevas, José Vicente, Santos, lucia, Rodríguez Fernández-Pacheco, Ana María, Manzano Manrique, Blanca Rosa Lourdes
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/31166
Acceso en línea:http://hdl.handle.net/10578/31166
Access Level:acceso abierto
Palabra clave:Anticancer
Chrysin
Cyclometalated
Platinum
TD-DFT
Anticancerígeno
Crisina
Ciclometalado
Platino
Descripción
Sumario:Luminescent platinum cyclometalated complexes are species of interest mainly due to their applications in the optoelectronic and biological fields, especially with regard to their anticancer activity. Given this level of interest, a series of cyclometalated (2-[2′-thienyl]pyridinate, thpy and 2-[2,4-difluorophenyl]pyridinate, dfppy) platinum complexes with N-donor, PTA (1,3,5-triaza-7-phosphaadamantane) or chrysin-derived ligands (incorporating piperidine, HL1, or morpholine, HL2, fragments) were synthesized. The complexes are luminescent with tunable emission wavelengths. Aggregation in solution was observed for [Pt(dfppy)L1], 5. Density-functional theory (DFT) studies provided descriptions of the highest occupied molecular orbital (HOMO) and least unoccupied molecular orbital (LUMO) characteristics and their influence on the photophysical properties. The orbitals of 5–6 were different in nature to those of 1–4. Time-dependent DFT (TD-DFT) calculations showed that for 1–4 the excited states S1 and T1 reflect metal-to-ligand charge transfer (MLCT) and ligand-centered (LC) (C^N) contributions while for 5–6 these states are an LC transition centered on L1 or L2. The speciation in DMSO and DMSO/H2O was evaluated. Biological studies showed that [Pt(thpy)Cl(Hthpy)], 1, [Pt(dfppy)Cl(Hdfppy)], 2, and 5 exert significant cytotoxic activity against human cervical (HeLa) and lung (A549) carcinoma cells. The cytotoxicity of 1 increased 2.84-fold upon irradiation (blue). Microscopy assays on 5 showed that this compound accumulates in cytoplasmic organelles, preferentially in mitochondria. Mitochondrial metabolism was disrupted by the activity of the complexes, leading to a decline in the adenosine triphosphate (ATP) cellular content. Overall, the results show an alternative anticancer activity for complexes 1, 2, and 5, which could be of great interest for the treatment of tumors with acquired resistance to conventional DNA-targeted anticancer drugs.