Synthesis, structural characterization and DNA interaction of new copper-terpyridine complexes

Anti-cancer property and DNA binding interaction of first row transition metal complexes: A decade update

Metal ions carry out a wide variety of functions, including acid-base/redox catalysis, structural functions, signaling, and electron transport. Understanding the interactions of transition metal complexes with biomacromolecules is essential for biology, medicinal chemistry, and the production of synthetic metalloenzymes. After the coincidental discovery of cisplatin, importance of the metal complexes in biochemistry became a top priority for inquiry. In this review, a decade update on various synthetic strategies to first row transition metal complex and their interaction with DNA through non-covalent binding are explored. Moreover, this effort provides an excellent analysis on the efficacy of theoretical and practical approaches to the systematic generation of new non-platinum based metallodrugs for anti-cancer therapeutics.

Self-Assembled Copper Metallogel Bearing Terpyridine and Its Application as a Catalyst for the Click Reaction in Water

Metallogels have attracted a great deal of interest because of their intriguing properties and applications in chemsensors, batteries, catalysis, and other fields. In this work, a novel ligand bearing terpyridine and hydroxyamine units was designed and synthesized. The ligand selectively gelated with copper ions in water by heating and cooling or sonication. Different physicochemical studies [Fourier transform infrared, ultraviolet-visible (UV-vis), electron paramagnetic resonance (EPR), scanning electron microscopy, X-ray diffraction, and rheology] were conducted to characterize the gels. We show that coordination interaction, π-π interaction, and noncovalent interaction had obvious effects on the properties of the gel. Additionally, a stable radical hydrogel could be obtained by ultrasound treatment, which was accompanied by color variation from green to blue. This was further confirmed by UV-vis and EPR experiments. Furthermore, the copper metallogels were developed as catalysts for the preparation of 1,2,3-triazole derivatives in water at 25 °C. Although various types of catalysts have been investigated, the use of metallogels as catalysts for the click reaction in water has been scarce. This strategy shows the process is simple, affords a high yield, and is "green" and economical.

Two DNA binding modes of a zinc-metronidazole and biological evaluation as a potent anti-cancer agent

A complex of metronidazole (MTZ) with zinc ion was synthesized and characterized by UV-Vis, Fourier transform infrared (FT-IR), ¹H-NMR, X-ray crystallography and thermal gravimetric-differential thermal analysis (TG-DTA). The cytotoxicity effect of the synthesized complex investigated over SKNMC, A549, MCF-7, and MCDK cell lines and the results have shown that it has high cytotoxic potential over cancer cell lines. In order to clarify the mechanism of cell cytotoxicity, the oxidative stress and binding of the complex to the calf thymus-DNA studied by evaluating the intrinsic binding constant and defining thermodynamic parameters of complex over the DNA accompanying with in silico molecular modeling method. For this purpose, the complex optimized at the B3LYP/LANL2DZ level and docked over the DNA structure. The results revealed that the metronidazole-zinc complex interacted with DNA via hydrogen binding and electrostatic interaction to the minor groove region and phosphate backbone of DNA, respectively.

Chromo-luminescent selective detection of fluoride ions by a copper(ii) bis(terpyridine) complex solution via a displacement approach

(1) For the first time a terpyrideine-Cu(ii) complex was used for the selective detection of F⁻ ions. (2) A dual mode detection method comprising chromo-luminescent techniques was used to evaluate the sensing mechanism. (3) The limit of detection was found to be 5.07 μM which is within the permissible level of F⁻ ions in drinking water according to the WHO.

Syntheses, crystal structures and DNA-binding activities of divalent Fe, Cu, Zn and Cd complexes with 4′-(furan-2-yl)-2,2′:6′,2″-terpyridine

Five coordination complexes [Fe(ftpy)2](ClO4)2·(H2O)2 (1), [Cu(ftpy)(NO3)(H2O)](NO3) (2), [Cu(ftpy)2]2(ClO4)4·(C2H5OH) (3), [Zn(ftpy)2]·(ClO4)2·(H2O)1.5 (4) and [Cd(ftpy)2]2(ClO4)4·(C2H5OH) (5) (ftpy=4′-(furan-2-yl)-2,2′:6′,2′-terpyridine) have been synthesized and characterized by IR, elemental analysis and single-crystal X-ray diffraction. With the exception of 4, all complexes adopt normal homoleptic [M(ftpy)2]2+ motifs. In the crystal, both hydrogen bonds and face-to-face interactions between furyl and pyridyl rings facilitate the construction of three-dimensional networks. The DNA-binding activities of the five complexes have been investigated by fluorescence emission titration at room temperature suggesting an intercalative mode for 1–3 with a relative order, 3>2>1, and a combined static and dynamic mode for 4 and 5.

Facile Synthesis of Fluorescent Conjugated Polyelectrolytes Using Polydentate Sulfonate as Highly Selective and Sensitive Copper(II) Sensors

Fluorescent conjugated polyelectrolytes represent an exciting area of research into new chemosensors. By virtue of their rapid electron and energy transfer paths, these highly correlated, one-dimensional systems have been depicted as "molecular wires" and show "million-fold" sensitivity compared to monomolecular sensor analogs. In this paper, a novel polyelectrolyte sensor, the ttp-PPESO₃, has been designed by incorporating terpyridine and sulfonate functional groups into the polyelectrolyte. This specifically tailored sensor has displayed remarkable quenching response toward copper(II) with a detection limit of 14.7 nM (0.93 ppb). It is capable of selectively screening copper without interference from 12 common cations. Molecular modeling suggests that binding occurs through a coordination interaction of the terpyridine and sulfonate. The additional multidentate nature from the sulfonate offers extraordinary chelating ability to the analyte. We anticipate that this unique binding mode will provide insight for the design of future more sensitive and selective systems.

Antimicrobial evaluation of new metallic complexes with xylitol active against P. aeruginosa and C. albicans: MIC determination, post-agent effect and Zn-uptake

Xylitol (xylH5) is metabolized via the pentose pathway in humans, but it is unsuitable as an energy source for many microorganisms where it produces a xylitol-induced growth inhibition and disturbance in protein synthesis. For this reason, xylitol is used in the prophylaxis of several infections. In the search of better antimicrobial agents, new copper and zinc complexes with xylitol were synthesized and characterized by analytical and spectrosco pic methods: Na2[Cu3(xylH−4)2]·NaCl·4.5H2O (Cu-xyl) and [Zn4(xylH−4)2(H2O)2]·NaCl·3H2O (Zn-xyl). Both copper and zinc complexes presented higher MIC against Pseudomona aeruginosa than the free xylitol while two different behaviors were found against Candida albicans depending on the complex. The growth curves showed that Cu-xyl presented lower activity than the free ligand during all the studied period. In the case of Znxyl the growth curves showed that the inhibition of the microorganism growth in the first stage was equivalent to that of xylitol but in the second stage (after 18 h) Zn-xyl inhibited more. Besides, the PAE (post agent effect)obtained for Zn-xyl and xyl showed that the recovery from the damage of microbial cells had a delay of 14 and 13 h respectively. This behavior could be useful in prophylaxis treatments for infectious diseases where it is important that the antimicrobial effect lasts longer. With the aim to understand the microbiological activities the analysis of the particle size, lipophilicity and Zn uptake was performed.

Homologous 1,3,5-triarylpyrazolines: synthesis, CH⋯π interactions guided self-assembly and effect of alkyloxy chain length on DNA binding properties

The synthesis, CH⋯π interactions-driven self-assembled structure and DNA binding properties (10⁵–10⁶M⁻¹binding constants) of new homologous 1,3,5-triaryl-2-pyrazolines are reported.