217-90-3Relevant academic research and scientific papers
DNA interactions, antitumor activities and radical scavenging properties of oxovanadium complexes with pyrazino[2,3-f][1,10]phenanthroline ligands
Zeng, Pengfei,He, Limin,Ye, Zhenfeng,Yang, Ning,Song, Yulan,Lu, Jiazheng
, p. 779 - 787 (2015)
Two unsymmetrical oxovanadium complexes [VO(satsc)(dpq)] (1) (satsc = salicylaldehyde thiosemicarbazone, dpq = pyrazino[2,3-f][1,10]phenanthroline) and [VO(hntdtsc)(dpq)] (2) (hntdtsc = 2-hydroxy-1-naphthaldehyde thiosemicarbazone) have been synthesized and characterized. Both complexes show strong interactions with calf thymus DNA through an intercalative model and can efficiently cleave pBR322 DNA after irradiation with light. Both complexes also exhibit high cytotoxicities against SH-SY5Y, MCF-7 and SK-N-SH cell lines. Complex 2 was found to have higher antitumor potency, DNA-binding affinity and DNA-cleaving ability than complex 1. The abilities of these complexes to scavenge hydroxy radicals were evaluated.
First aggregation-induced emission of a Tb(iii) luminophore based on modulation of ligand-ligand charge transfer bands
Fushimi, Koji,Hasegawa, Yasuchika,Kitagawa, Yuichi,Kumagai, Marina,Nakanishi, Takayuki
, p. 2431 - 2436 (2020)
Herein the aggregation-induced emission (AIE) of a Tb(iii) complex is reported for the first time. The Tb(iii) complex is composed of three anionic ligands (acac: acetylacetonate) and one large hetero-π-conjugated neutral ligand (dpq: dipyrido[3,2-f:2′,3′-h]quinoxaline). The formation of a crystalline J-aggregate of the Tb(iii) complex (CJ-Tb(iii)) was characterized by X-ray crystal structure analysis and absorption spectra. A crystalline H-aggregate (CH-Tb(iii)) was also prepared using the ligand steric effect (tmh: 2,2,6,6-tetramethyl-3,5-heptanedionate). The emission and AIE properties of CJ-Tb(iii) were evaluated using emission spectra, lifetime, and quantum yields, whereas CH-Tb(iii) did not emit photons. Density functional theory calculations predict that the AIE originates from the modulation of ligand-to-ligand charge transfer bands through J-aggregation.
Synthesis and characterization of ruthenium complexes with substituted pyrazino[2,3-f][1,10]-phenanthroline (= RPPL; R = ME, COOH, COOME)
Delgadillo, Alvaro,Romo, Paola,Leiva, Ana Maria,Loeb, Barbara
, p. 2110 - 2120 (2003)
A series of substituted pyrazino[2,3-f][1,10]-phenanthroline (Rppl) ligands (with R = Me, COOH, COOMe) were synthetized (see 1-4 in Scheme 1). The ligands can be visualized as formed by a bipyridine and a quinoxaline fragment (see A and B). Homoleptic [Ru(R1ppl)3](PF6)2 and heteropleptic [Ru(R1ppl){(R2)2bpy}2] (PF6)2 (R1 = H, Me, COOMe and R2 = H, Me) metal complexes 5-7 and 8-13, respectively, based on these ligands were also synthesized and characterized by conventional techniques (Schemes 2 and 3, resp.). In the heteroleptic complexes, the R1-ppl ligand reduces at a less-negative potential than the bpy ligand, reflecting the acceptor property conferred by the quinoxaline moiety. The potentiality of some of these complexes as solar-cell dyes is discussed.
Ni(II) curcumin complexes for cellular imaging and photo-triggered in vitro anticancer activity
Banaspati, Atrayee,Raza, Md Kausar,Goswami, Tridib K.
, (2020/08/11)
Nickel(II) complexes [Ni(cur)(L)2](OAc) (1-3) where L is N,N-donor heterocyclic bases namely 1,10-phenanthroline (phen in 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq in 2), dipyrido[3,2-a:2′,3′-c]phenazine (dppz in 3) and Hcur is curcumin were
Ru(ii) photosensitizers competent for hypoxic cancersviagreen light activation
Ballester, Francisco J.,Bautista, Delia,Ortega, Enrique,Ruiz, José,Santana, M. Dolores
, p. 10301 - 10304 (2020/09/16)
A family of five heteroleptic complexes [Ru(C^N)(N^N)2][PF6] (HC^N = methyl 1-butyl-2-arylbenzimidazolecarboxylate; N^N = polypyridine) has been synthesized to act as biologically-compatible green light photosensitizers (PSs) with phototherapeutic indexes (PIs) up to higher than 700 under hypoxia (2% O2) in HeLa cancer cells under short time of irradiation.
On the development of a new approach to the design of lanthanide-based materials for solution-processed OLEDs
Kozlov, Makarii I.,Aslandukov, Andrey N.,Vashchenko, Andrey A.,Medvedko, Alexey V.,Aleksandrov, Alexey E.,Grzibovskis, Raitis,Goloveshkin, Alexander S.,Lepnev, Leonid S.,Tameev, Alexey R.,Vembris, Aivars,Utochnikova, Valentina V.
, p. 17298 - 17309 (2019/12/02)
The targeted design of lanthanide-based emitters for solution-processed organic light-emitting diodes (OLEDs) resulted in obtaining an NIR OLED with one of the highest efficiencies among ytterbium-based solution-processed OLEDs (30 μW W-1). The design was aimed at the combination of high luminescence efficiency with solubility and charge carrier mobility. The latter was achieved thanks to the introduction of the purposefully selected neutral ligands, which combine electron mobility and the ability to sensitize lanthanide luminescence. Besides, the HOMO and LUMO energies and charge carrier mobility of solution-processed thin films of coordination compounds were measured experimentally for the first time, and novel highly luminescent europium-based materials with PLQYs of up to 80% and purely NIR luminescent ytterbium complexes were obtained.
A series of blue-green-yellow-red emitting Cu(I) complexes: Molecular structure and photophysical performance
Zhang, Liming,Zuo, Qinghui
, (2019/06/25)
In this work, we designed a series of [Cu(N–N)(PPh3)2]BF4 complexes with different optical edge values and emission colors from blue to red, where N–N and PPh3 denoted a diamine ligand and triphenylphosphine, respectively. Six N–N ligands with various conjugation chains (short π chain, modest π chain and long π chain) were selected. A systematical comparison between these Cu(I) complexes was performed, so that the correlation between N–N structure and [Cu(N–N)(PPh3)2] photophysical performance was tentatively discussed. Their single crystal structure was found consistent with literature ones, forming a typical tetrahedral coordination geometry. Density functional theory calculation indicated that their onset electronic transition showed a mixed character of metal-to-ligand-charge-transfer and ligand-to-ligand-charge-transfer. Detailed analysis on photophysical parameters suggested that the absorption edge of [Cu(N–N)(PPh3)2]BF4 complex was controlled by conjugation length in diamine ligand. A wide absorption edge needed a short conjugation chain in diamine ligand. Similar tendency was found for their emission spectra. In addition, a long conjugation chain in diamine ligand widened emission spectra obviously. Emission dynamics showed slim correlation with diamine ligand conjugation length since the excited state was controlled mainly by dynamic procedure and steric factor of diamine ligands.
Increasing the triplet lifetime and extending the ground-state absorption of biscyclometalated Ir(III) complexes for reverse saturable absorption and photodynamic therapy applications
Wang, Chengzhe,Lystrom, Levi,Yin, Huimin,Hetu, Marc,Kilina, Svetlana,McFarland, Sherri A.,Sun, Wenfang
, p. 16366 - 16378 (2016/10/31)
The synthesis, photophysics, reverse saturable absorption, and photodynamic therapeutic effect of six cationic biscyclometalated Ir(iii) complexes (1-6) with extended π-conjugation on the diimine ligand and/or the cyclometalating ligands are reported in this paper. All complexes possess ligand-localized 1π,π? absorption bands below 400 nm and charge-transfer absorption bands above 400 nm. They are all emissive in the 500-800 nm range in deoxygenated solutions at room temperature. All complexes exhibit strong and broad triplet excited-state absorption at 430-800 nm, and thus strong reverse saturable absorption for ns laser pulses at 532 nm. Complexes 1-4 are strong reverse saturable absorbers at 532 nm, while complex 6 could be a good candidate as a broadband reverse saturable absorber at 500-850 nm. The degree of π-conjugation of the diimine ligand mainly influences the 1π,π? transitions in their UV-vis absorption spectra, while the degree of π-conjugation of the cyclometalating ligand primarily affects the nature and energies of the lowest singlet and emitting triplet excited states. However, the lowest-energy triplet excited states for complexes 3-6 that contain the same benzo[i]dipyrido[3,2-a:2′,3′-c]phenazine (dppn) diimine ligand but different cyclometalating ligands remain the same as the dppn ligand-localized 3π,π? state, which gives rise to the long-lived, strong excited-state absorption in the visible to the near-IR region. All of the complexes exhibit a photodynamic therapeutic effect upon visible or red light activation, with complex 6 possessing the largest phototherapeutic index reported to date (>400) for an Ir(iii) complex. Interactions with biological targets such as DNA suggest that a novel mechanism of action may be at play for the photosensitizing effect. These Ir(iii) complexes also produce strong intracellular luminescence that highlights their potential as theranostic agents.
Copper phenanthrene oxidative chemical nucleases
Molphy, Zara,Prisecaru, Andreea,Slator, Creina,Barron, Niall,McCann, Malachy,Colleran, John,Chandran, Deepak,Gathergood, Nicholas,Kellett, Andrew
, p. 5392 - 5404 (2014/06/09)
Here we report the synthesis and isolation of a series of bis-chelate Cu2+ phenanthroline-phenazine cationic complexes of [Cu(DPQ)(Phen)]2+, [Cu(DPPZ)(Phen)]2+, and [Cu(DPPN)(Phen)]2+ (where Phen = 1,10-phenanthroline, DPQ = dipyridoquinoxaline, DPPZ = dipyridophenazine, and DPPN = benzo[i] dipyridophenazine). These compounds have enhanced DNA recognition relative to the well-studied chemical nuclease, [Cu(Phen)2]2+ (bis-Phen), with calf thymus DNA binding constants of DPQ and DPPZ agents (～107 M(bp)-1) being the highest currently known for Cu2+ phenanthrene compounds. Complex DNA binding follows DPQ ≈ DPPZ > DPPN > bis-Phen, with fluorescence quenching and thermal melting experiments on poly[d(A-T)2] and poly[d(G-C)2] supporting intercalation at both the minor and major groove. Phenazine complexes, however, show enhanced targeting and oxidative cleavage on cytosine-phosphate-guanine- rich DNA and have comparable in vitro cytotoxicity toward the cisplatin-resistant ovarian cancer line, SKOV3, as the clinical oxidative DNA-damaging drug doxorubicin (Adriamycin). In this study we also describe how a novel "on-chip" method devised for the Bioanalyser 2100 was employed to quantify double-stranded DNA damage, with high precision, by the complex series on pUC19 DNA (49% A-T, 51% G-C). Both DPQ and bis-Phen complexes are highly efficient oxidizers of pUC19, with DPQ being the most active of the overall series. It is apparent, therefore, that oxidative chemical nuclease activity on homogeneous canonical DNA is not entirely dependent on dynamic nucleotide binding affinity or intercalation, and this observation is corroborated through catalytic interactions with the superoxide anion radical and Fenton breakdown of hydrogen peroxide.
A series of [Cu(N-N)(P-P)]BF4 complexes: Luminescence quenching caused by electron-configuration transformation in excited state
Zhang, Liming,Yue, Shumei,Li, Bin,Fan, Di
experimental part, p. 225 - 232 (2012/05/20)
In this paper, we report a series of [Cu(N-N)(P-P)]BF4 complexes based on two phosphorous ligands and three 1,10-phenanthrolin derived diimine ligands, including their syntheses, characterizations, crystal structures. Their photophysical properties were experimentally measured and theoretically analyzed by time-dependent density functional theory (TD-DFT). It is found that the introduction of too many fused phenyl rings into diimine ligand leads to luminescence absence of corresponding [Cu(N-N)(P-P)]+ complexes at room temperature. A detailed analysis suggests that the thermal activated electron-configuration transformation between the [Cu(N-N)(P-P)]+ triplet metal-to-ligand-charge-transfer (3MLCT) state and the lowest lying excited state of its diimine ligand (3LC) is responsible for the luminescence quenching.
