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With the aim of gaining new insight into the underlying apoptosis mechanisms and in vivo efficacy of cyclometalated Ir(III) complexes as metalodrugs, six new cyclometalated Ir(III)–quinoline complexes, [Ir(1a)(2pq)2] (2a), [Ir(1b)(2pq)2] (2b), [Ir(1c)(2pq)2] (2c), [Ir(1d)(2pq)2] (2d), [Ir(1e)(2pq)2] (2e), and [Ir(1f)(2pq)2] (2f) (2pq = 2-phenylisoquinoline), have been synthesized using 5,7-dihalo-8-hydroxylquinoline ligands (1a–1f) and [Ir(2pq)2Cl]2 precursors and characterized. Complexes 2a–2f have shown potent anticancer activity against cisplatin-resistant SK-OV-3/DDP and A549/DDP cells (IC50 = 0.11–1.83 μM), following the order 2e > 2f > 2b > 2c > 2d > 2a. Confocal microscopy images suggest that 2e and 2b could act as red-color probes for specific cell imaging and efficiently initiate apoptosis and autophagy in the mitochondria, cell cytosol, and nucleus. Overexpression of beclin1, caspase-9, cytochrome c, LC3II, and apaf-1; inhibition of p62, cyclin D1, cyclin A2, and CDK2; and a substantial rapid accumulation suggest a paraptotic mode of cell death induced by autophagy, DNA damage, and mitochondrial stress. In addition, the inhibitory rate of 2e on A549/DDP tumor growth was 64.1% at a concentration of 10.0 mg kg−1, which is clearly higher than that of cisplatin. According to the biological assay, the cyclometalated Ir(III)–quinoline complex 2e exhibited a higher anticancer effect than 2b, which may be associated with the electronic effect of the methyl group of the 1e ligand of 2e playing a key role in the mechanism. [ABSTRACT FROM AUTHOR]

Synthetic, structural, photophysical, and electrochemical study of [Ir(ppy)2(py)2](BF4) (1(BF4)) and four di‐N–N‐bridged complexes of [Ir(ppy)2(bpa)]2(BF4)2 (2A(BF4)2), [Ir(ppy)2((cis‐bpe))]2(BF4)2 (2B(BF4)2), [Ir(ppy)2(tmp)]2(BF4)2 (2C(BF4)2), and [Ir(ppy)2(bpy)]4(BF4)4 (3(BF4)4) are described with Hppy = 2‐phenylpyridine, py = pyridine, N–N = dipyridyl ligands of 1,2‐bis(4‐pyridyl)ethane (bpa), cis‐1,2‐bis(4‐pyridyl)ethylene (cis‐bpe), 1,3‐di(4‐pyridyl)propane (tmp), and 4,4'‐dipyridine (bpy). Five single‐crystal structures of 1(PF6), 2A(NO3)2, 2A(PF6)2, 2B(PF6)2, and 3(NO3)4 were determined, supporting the dibridged structures and presence of a variety of stereoisomers. Application of four luminescent complexes, 1(BF4), 2A(BF4)2, 2C(BF4)2, and 3(BF4)4, in solid‐state light‐emitting electrochemical cells (LECs) is reported. The work demonstrates an effective approach to realize efficient LECs based on dibridged di‐ and multinuclear cationic transition‐metal complexes with a suitably long alkyl spacer in the bridging ligand. [ABSTRACT FROM AUTHOR]

[Display omitted] • • Mn(II) complex 1 with 8-hydroxyquinoline-N-oxide was firstly synthesized. • • Mn(II) complex 1 showed high in vitro antitumor activity toward A549/DDP cells. • • Mn(II) complex 1 can cause mitochondrial dysfunction. A new manganese(II) complex bearing an 8-hydroxyquinoline- N -oxide (HNQ) ligand, i.e., [Mn(HNQ) 2 (CH 3 OH) 2 Cl 2 ] (1), was synthetized and fully characterized by single-crystal X-ray diffraction, infrared spectroscopy, electrospray ionization mass spectrometry, and elemental analysis, which revealed that Mn(II) complex 1 is a six-coordinated mononuclear compound. The anticancer activity of Mn(II) complex 1 against A549/DDP and A549 cancer cells and HL-7702 normal cells was tested and compared with that of MnCl 2 ⋅4H 2 O, cisplatin, and HNQ. Mn(II) complex 1 displayed potent cytotoxic activity, especially against A549/DDP tumor cells, with IC 50 values of 0.02 ± 0.01 μM, whereas it was practically inactive against HL-7702 normal cells. Mechanistic studies indicated that the cytotoxic activity of Mn(II) complex 1 proceeds via induction of mitochondria-mediated intrinsic apoptosis in A549/DDP cells. [ABSTRACT FROM AUTHOR]

Following publication of the original article [1], the authors reported an error in Schemes 1 and 2 and repeated line in subsection "Bis(ligand) nickel(II) chelate (NiL12)". [ABSTRACT FROM AUTHOR]

Background: The general approach to the synthesis of metal complexes begins with ligand synthesis, followed by ligand reaction with metal salts to afford organometallic complexes. Our research group first reported a one-pot multicomponent synthesis of chiral oxazolinyl–zinc complexes, in the presence of a large amount of ZnCl2 (0.4–2.6 equiv.), with the yields of some products reaching 90%. Results: Our prior strategy was extended to use copper, cobalt, nickel, manganese, palladium or platinum salts as the third component. The one-step method used 1.0 equivalent of a metal salt, such as M(OAc)2·nH2O or MCl2·nH2O (M: Cu, Co, Ni, Pd or Pt, n = 1, 2 or 4), as a reagent to generate chiral salicyloxazoline complexes 1–8 in the reaction of 2-cyanophenol with different d- and l-amino alcohols. Conclusion: Complexes 1–8 were obtained using a one-pot method with a sequential strategy. The reaction outcome was demonstrated for three-component reactions between metal salts, amino alcohols and 2-hydroxybenzonitrile to afford organometallic complexes in good yields (65–95%). [ABSTRACT FROM AUTHOR]