A Novel Platinum-based Compound with Preferential Cytotoxic Activity against a Panel of Cancer Cell Lines.

PURPOSE: Cisplatin as a platinum (Pt)-based chemotherapeutic compound is commonly applied for the treatment of several types of cancer. Nonetheless, drug resistance and severe adverse effects have been observed upon using cisplatin. Here, we have explored the cytotoxicity of novel Pt-based compounds on several cancer cell lines. METHODS: Five synthetic Pt compounds as well as cisplatin were investigated by XTT assay to determine their cytotoxicity against cell lines originated from prostate, ovary, and breast cancers at different time periods at various concentrations. Additionally, the apoptosis rate in cell lines was determined using flow cytometry. Binding to DNA was investigated through spectrophotometric and viscometric studies. RESULTS: With the exception of one compound, all of the Pt-complexes effectively killed the prostate cancer cell lines (i.e. PC-3 and DU 145). One compound, [Pt(2,2'- dipyridylamine)Cl4].DMF, was chosen as the most potent compound due to its high selective cytotoxic activity and its cytotoxicity was further tested and compared with that of cisplatin on SKOV-3, Caov-4, MDA-MB-231, and MCF7 cell lines. [Pt(2,2'-dipyridylamine)Cl4].DMF had a higher selective cytotoxic capacity in comparison with cisplatin at higher concentrations and longer culture periods. Furthermore, as related to apoptosis induction, treatment with [Pt(2,2'-dipyridylamine)Cl4 ].DMF was significantly more effective than that of cisplatin in five out of six examined cell lines. [Pt(2,2'-dipyridylamine)Cl4].DMF was shown to intercalate into DNA. CONCLUSIONS: The current study introduced a novel Pt-based complex with highly selective and potent in vitro anti-tumor impacts superior to those of cisplatin, a conventional chemotherapeutic agent. [Pt (2,2'-dipyridylamine)Cl4].DMF could be regarded as a promising antitumor agent in future investigations.

A Novel Platinum-based Compound with Preferential Cytotoxic Activity against a Panel of Cancer Cell Lines

PURPOSE: Cisplatin as a platinum (Pt)-based chemotherapeutic compound is commonly applied for the treatment of several types of cancer. Nonetheless, drug resistance and severe adverse effects have been observed upon using cisplatin. Here, we have explored the cytotoxicity of novel Pt-based compounds on several cancer cell lines. METHODS: Five synthetic Pt compounds as well as cisplatin were investigated by XTT assay to determine their cytotoxicity against cell lines originated from prostate, ovary, and breast cancers at different time periods at various concentrations. Additionally, the apoptosis rate in cell lines was determined using flow cytometry. Binding to DNA was investigated through spectrophotometric and viscometric studies. RESULTS: With the exception of one compound, all of the Pt-complexes effectively killed the prostate cancer cell lines (i.e. PC-3 and DU 145). One compound, [Pt(2,2'- dipyridylamine)Cl4].DMF, was chosen as the most potent compound due to its high selective cytotoxic activity and its cytotoxicity was further tested and compared with that of cisplatin on SKOV-3, Caov-4, MDA-MB-231, and MCF7 cell lines. [Pt(2,2'-dipyridylamine)Cl4].DMF had a higher selective cytotoxic capacity in comparison with cisplatin at higher concentrations and longer culture periods. Furthermore, as related to apoptosis induction, treatment with [Pt(2,2'-dipyridylamine)Cl4 ].DMF was significantly more effective than that of cisplatin in five out of six examined cell lines. [Pt(2,2'-dipyridylamine)Cl4].DMF was shown to intercalate into DNA. CONCLUSIONS: The current study introduced a novel Pt-based complex with highly selective and potent in vitro anti-tumor impacts superior to those of cisplatin, a conventional chemotherapeutic agent. [Pt (2,2'-dipyridylamine)Cl4].DMF could be regarded as a promising anti-tumor agent in future investigations.

A novel magnetic ion imprinted nano-polymer for selective separation and determination of low levels of mercury(II) ions in fish samples.

In this work a novel ion imprinted polymer (IIP) based on N-(pyridin-2-ylmethyl)ethenamine (V-Pic) was coated on Fe3O4 nano-particles and characterized by thermal gravimetric and differential thermal analysis (TG/DTA), IR spectroscopy, Scanning electron microscopy (SEM) and also elemental analysis. The application of this novel magnetic sorbent was investigated in rapid extraction, preconcentration and also determination of trace amounts of Hg(II) ions by inductively coupled plasma-optical emission spectrometry (ICP-OES). Effect of various parameters such as sample pH, adsorption time and desorption time, maximum capacity and also eluent type and concentration was investigated in this study. The relative standard deviation (RSD%) and limit of detection (LOD) of the method were found to be 1.47% and 0.03 ng mL(-1), respectively. The amounts of mercury in some standard reference materials was Also determined using this sorbent in order to confirm the accuracy of this method. Finally, this sorbent was successfully applied for determination of low levels of Hg(II) ions in various fish samples.

The influence of steric effects on intramolecular secondary bonding interactions; cytotoxicity in gold(III) bithiazole complexes.

The reaction of two sterically different bithiazole ligands with gold(III) was investigated. Our results show that, depending on the ligand used, different coordination geometries around the gold(III) center were achieved. Where sterically unhindered 4bt ligand was used, regular square-planar compound [Au(4bt)Cl2][AuCl4] (1) is isolated, while in the case of sterically hindered dm4bt ligand, the interplay between the steric effect and the intramolecular secondary bonding interaction leads to the formation of disordered square-pyramidal geometry in [Au(dm4bt)Cl3] (2). Furthermore, the steric influence of the methyl group in the ligand plays an important role in the cytotoxicity of the compound in different cultures. Interestingly, compound 1 is more potent to kill a breast cancer cell line than cisplatin (13 times), and its cytotoxicity arises from the cationic part, [Au(4bt)Cl2](+).

Tris(ethyl-enediamine-κ(2)N,N')nickel(II) bis-(dimethyl phosphate).

In the title compound, [Ni(C(2)H(8)N(2))(3)][O(2)P(OCH(3))(2)](2), the Ni(II) atom is six-coordinated in a distorted octa-hedral geometry by six N atoms from three ethyl-enediamine ligands. The P atoms of the anions adopt a distorted tetra-hedral geometry. In the crystal, inter-molecular N-H⋯O and C-H⋯O hydrogen bonds link the cations and anions into a three-dimensional network.

Bis(ethyl-enediamine-κ(2)N,N')bis-(methanol-κO)copper(II) benzene-1,4-dicarboxyl-ate methanol disolvate.

In the cation of the title compound, [Cu(C(2)H(8)N(2))(2)(CH(3)OH)(2)](C(8)H(4)O(4))·2CH(3)OH, the Cu(II) atom lies on an inversion centre. The four N atoms of two ethyl-enediamine ligands around the Cu(II) atom form the equatorial plane, while two methanol O atoms in the axial positions complete a Jahn-Teller distorted octa-hedral coordination. The benzene-1,4-dicarboxyl-ate anion is centrosymmetric. In the crystal, C-H⋯O, N-H⋯O and O-H⋯O hydrogen bonds link the cations, the anions and the methanol solvent mol-ecules.

2,9-Dimethyl-1,10-phenanthrolin-1-ium tetra-chloridoferrate(III) methanol monosolvate.

In the title compound, (C14H13N2)[FeCl4]·CH3OH, the 2,9-dimethyl-1,10-phenanthrolin-1-ium cation, FeCl4 ⁻ anion and methanol solvent mol-ecule lie on a twofold rotation axis. Due to symmetry, the H atom on the N atom of the cation is half-occupied. In the anion, the Fe(III) atom has a tetra-hedral geometry. H atoms of the methanol mol-ecule are disordered over two sets of sites around the twofold axis. In the crystal, π-π contacts between the pyridine rings and between the pyridine and benzene rings [centroid-centroid distances = 3.6535 (16) and 3.5522 (17) Å] and inter-molecular O-H⋯N and N-H⋯O hydrogen bonds stabilize the structure.

Pyridine-functionalized Fe3O4 nanoparticles as a novel sorbent for the preconcentration of lead and cadmium ions in tree leaf as a bioindicator of urban traffic pollution.

We have developed a facile and highly sensitive sorbent for cadmium and lead ions. It is based on Fe3O4 nanoparticles functionalized with a derivative of picoline and was characterized by scanning electron microscopy, differential thermographic analysis, and elemental analysis. The material can be applied to the preconcentration of lead and cadmium ions. Factors such as the type, concentration and volume of eluent, the pH of the sample solution, the time for extraction, and the volume of the sample were studied. The effects of a variety of ions on preconcentration and recovery of these ions were also investigated. The ions were determined by FAAS, and the limits of detection are <0.8 and <0.061 µg L⁻¹ for lead and cadmium, respectively. Recoveries and precisions are >98.0 % and <1.3 %, respectively. The method was validated by analyzing several certified leaf reference materials.

(2E,6E)-2,6-Bis(2,6-dichloro-benzyl-idene)-cyclo-hexa-none.

The title compound, C(20)H(14)Cl(4)O, was prepared by the reaction of 2,6-dichloro-benzaldehyde and cyclo-hexa-none. In the mol-ecule, the central cyclo-hexa-none ring adopts an envelope conformation, while the terminal benzene rings make a dihedral angle of 57.87 (9)°.

N-[2-(N-Cyclo-hexyl-carbamo-yl)propan-2-yl]-N-(2-iodo-phen-yl)prop-2-ynamide.

In the title compound, C(19)H(23)IN(2)O(2), the cyclo-hexane ring adopts a chair conformation, and the mean plane of the propiolamide unit is approximately perpendicular to the benzene ring [dihedral angle = 88.12 (13)°]. Weak intra-molecular C-H⋯O hydrogen bonding is observed between the carbonyl group and the benzene ring. In the crystal, classical N-H⋯O hydrogen bonds and weak C-H⋯O inter-actions are present.

Solution and solid state characterization of oxo-centered trinuclear iron(III) acetate complexes [Fe3(µ3-O)(µ-OAc)6(L)3]+.

[Fe(3)(µ(3)-O)(µ-OAc)(6)(py)(3)][FeBr(4)](2)[py·H], complex (1), (OAc is acetate) was prepared from the reaction of FeBr(3) with pyridine in 1.2 molar aqueous HBr and 2.4 molar aqueous CH(3)COOH. Recrystallization of 1 in acetonitrile produced the [Fe(3)(µ(3)-O)(µ-OAc)(6)(py)(3)][FeBr(4)] complex (2). Both complexes were characterized by IR and (1)H NMR spectroscopies and their structures were studied using the single-crystal diffraction method. There is a lack of thorough characterization of the titled compounds in solution. Paramagnetic (1)H NMR is introduced as a good probe for the characterization of a family of titled compounds in solution when the L ligand coordinated to iron varies as: CH(3)OH, CH(3)CN, DMSO, H(2)O, py and acetone.

2,5-Bis(pyridinium-2-yl)-3,6-bis-(2-pyrid-yl)pyrazine bis-[tetra-chlorido-aurate(III)].

In the title compound, (C(24)H(18)N(6))[AuCl(4)](2), the cation is located on an inversion center. Each of the two independent Au(III) ions lies on an inversion center and has a distorted square-planar geometry. In the crystal, inter-molecular C-H⋯Cl hydrogen bonds, π-π inter-actions [centroid-centroid distances = 3.5548 (16) and 3.7507 (16) Å] and Au⋯π inter-actions [Au⋯centroid distance = 3.6424 (10) Å] are effective in the stabilization of the structure, resulting in the formation of a supra-molecular structure. Intra-molecular N-H⋯N hydrogen bonds are present in the cation.

(4,5-Diaza-fluoren-9-one-κN,N')bis-(thio-cyanato-κS)mercury(II).

In the title compound, [Hg(NCS)(2)(C(11)H(6)N(2)O)], the Hg(II) atom, lying on a twofold rotation axis, is four-coordinated in a distorted tetra-hedral geometry by an N,N'-bidentate diaza-fluoren-9-one ligand and two thio-cyanate anions. In the crystal, inter-molecular C-H⋯N and C-H⋯O hydrogen bonds are effective in the stabilization of the structure.

Synthesis, characterization, mechanochromism and photochromism of [Fe(dm4bt)3][FeCl4]2 and [Fe(dm4bt)3][FeBr4]2, along with the investigation of steric influence on spin state.

The complexes [Fe(dm4bt)(3)][FeCl(4)](2) (1) and [Fe(dm4bt)(3)][FeBr(4)](2) (2) were prepared from the reaction of 2,2'-dimethyl-4,4'-bithiazole (dm4bt) with FeCl(3)·6H(2)O and FeBr(3), respectively, in methanol. Both complexes were characterized by IR, UV-Vis and (1)H NMR spectroscopy and their structures were studied by single-crystal diffraction. The methylated bithiazole led to high spin Fe(II) centers in the octahedral cation part of complexes 1 and 2 with Fe-N distance of 2.220 Å, in spite of the low spin octahedral Fe(II) complexes with unsubstituted bithiazole ligands. Crystal structure determination of 2 was performed at 90, 120 and 298 K. Temperature reduction to 90 K resulted in a decrease in the Fe-N bond length to 2.206 Å which is still in the range of high spin Fe(II). Complex 1 shows a reversible mechanochromic effect from the crystalline phase to powder form from red to yellow; it also displays reversible photochromism from yellow to green in solution under sunlight. The magnetic behaviour of the complexes was also studied at 2-300 K. The temperature dependence of χ(m)T curves for the two forms of 1, crystal and powder, demands some changes in their magnetic behavior, causing different colors i.e. red and yellow. At low temperatures, χ(m)T decreases where the decrease starts at around 65 K for compound 1, and at around 100 K for compound 2, due to different counterions. The two complexes exhibit antiferromagnetism at around 4 K.

(6,6'-Dimethyl-2,2'-bipyridine-κN,N')diiodidomercury(II).

In the title complex, [HgI(2)(C(12)H(12)N(2))], the Hg(II) atom has a distorted tetra-hedral coordination formed by two N atoms of the 6,6'-dimethyl-2,2'-bipyridine ligand and two terminal I atoms [N-Hg-N = 70.1 (2) and I-Hg-I = 130.59 (3)°]. The crystal packing features π-π contacts between the pyridine rings of adjacent mol-ecules [centroid-centroid distance = 3.773 (5) Å] and also between a pyridine ring of one mol-ecule and the five-membered chelate ring of an adjacent mol-ecule [centroid-centroid distance = 3.668 (4) Å].

Tris(4,4'-bi-1,3-thia-zole-κN,N')iron(II) tetra-bromidoferrate(III) bromide.

In the [Fe(4,4'-bit)(3)](2+) (4,4'-bit is 4,4'-bi-1,3-thia-zole) cation of the title compound, [Fe(C(6)H(4)N(2)S(2))(3)][FeBr(4)]Br, the Fe(II) atom (3 symmetry) is six-coordinated in a distorted octa-hedral geometry by six N atoms from three 4,4'-bit ligands. In the [FeBr(4)](-) anion, the Fe(III) atom (3 symmetry) is four-coordinated in a distorted tetra-hedral geometry. In the crystal, inter-molecular C-H⋯Br hydrogen bonds and Br⋯π inter-actions [Br⋯centroid distances = 3.562 (3) and 3.765 (2) Å] link the cations and anions, stabilizing the structure.

2,2'-Azanediyl-diethanaminium pyridine-2,5-dicarboxyl-ate.

The crystal structure of the title compound, C(4)H(15)N(3) (2+)·C(7)H(3)NO(4) (2-), consists of diethyl-enetriaminium (2,2'-azanediyl-diethanaminium) cations and pyridine-2,5-dicarboxyl-ate anions, which are linked by N-H⋯O, N-H⋯N and C-H⋯O hydrogen bonds. C-H⋯π inter-actions are also observed. In the anion, the carboxyl-ate groups are oriented at dihedral angles of 11.04 (15) and 6.31 (14)° with respect to the pyridine ring.

(4,4'-Dimethyl-2,2'-bipyridine-κN,N')(dimethyl sulfoxide-κO)diiodidocadmium(II).

In the title compound, [CdI(2)(C(12)H(12)N(2))(C(2)H(6)OS)], the Cd(II) cation is coordinated by two N atoms from a dimethyl-bipyridine ligand, one O atom from a dimethyl sulfoxide mol-ecule and two I(-) anions in a distorted trigonal-bipyramidal geometry. Intra-molecular C-H⋯O hydrogen bonding and inter-molecular π-π stacking between parallel pyridine rings [centroid-centroid distance = 3.658 (3) Å] are present in the crystal structure.

catena-Poly[[(5,5'-dimethyl-2,2'-bi-pyridine-κN,N')cadmium(II)]-di-µ-iodido].

In the title coordination polymer, [CdI(2)(C(12)H(12)N(2))](n), the Cd(2+) ion lies on a twofold rotation axis: it is six-coordinated in a distorted cis-CdN(2)I(4) octa-hedral geometry by two N atoms from a chelating 5,5'-dimethyl-2,2'-bipyridine ligands and four bridging iodide anions. The bridging function of the iodide ions leads to a chain structure propagating in [001].

Bis(tribenzyl-ammonium) tetra-chloridoaurate(III) chloride.

In the title compound, (C(21)H(22)N)(2)[AuCl(4)]Cl, the Au(III) atom adopts a square-planar coordination geometry defined by four chloride ions. In the crystal structure, inter-molecular N-H⋯Cl hydrogen bonds link the organic cations and the uncoordinated chloride ion.