Structural characterization and antitumor activity of platinum(II) complexes with phenothiazine and N-methylphenothiazine

Cisplatin is one of the most used anticancer agents, and along with carboplatin and oxaliplatin, is a part of more than 50% of clinically applied anticancer regimens [1]. However, the side effects of cisplatin are severe and include dose-limiting toxicity, such as neurotoxicity, nephrotoxicity and ototoxicity. Platinum(II) complexes with different structure from cisplatin provide many opportunities for design of novel antitumor drugs with improved pharmacological properties. Considering this, in the present study, new platinum(II) complexes with phenothiazine (phtz) and N-methylphenothiazine (N-Mephtz), [PtCl2(phtz)(CH3CN)] (1) and [PtCl2(N-Mephtz)(CH3CN)] (2), were synthesized. These complexes were characterized by elemental microanalysis, NMR (1H and 13C) and IR spectroscopic measurements, while the structure of complex 1 was determined by single-crystal X-ray diffraction analysis. The antitumor activity of the platinum(II) complexes was tested in vitro against a panel of human cancer cell lines, including A549 (lung cancer), A375 (melanoma, skin cancer), MDA-MB-231 (breast cancer), and HCT116 (colon cancer). To check the selectivity of the synthesized complexes 1 and 2, a healthy MRC-5 cell line (lung fibroblasts) was also included in this study.Book of abstract:16th International Symposium on Applied Bioinorganic Chemistry (16-ISABC) 11-14th June University of Ioannina Greec

Near-infrared spectroscopy study for determination of adsorbed acetochlor in the organic and inorganic bentonites

NIR spectroscopy is used to determine acetochlor herbicide adsorption on Na-montmorillonite (NaP) and organically modified montmorillonite (NaOM). Both montmorillonites NIR spectra shows bands at 7061 and 6791 cm(-1). Organo-montmorillonite is characterised by two emphasized bands at 5871 and 5667 cm(-1) that are attributed to the fundamental overtones of the mid-IR bands at 2916 and 2850 cm(-1). Bands at 6017 and 6013 cm(-1) are attributed to acetochlor adsorbed to organo-montmorillonite and Na-montmorillonite, which is confirmed by X-ray powder diffraction (XRPD). Greater quantity of acetochlor is adsorbed to organo-clays compared to non-modified montmorillonite. Acetochlor poses high risk to environmental contamination. Organo-clays are the most useful for removing acetochlor from water and soil

NIR and MIR spectroscopic characteristics of hydrophilic and hydrophobic bentonite treated with sulphuric acid

Near-infrared (NIR) and mid-infrared (MIR) spectroscopy are irreplaceable methods for characterization of bentonites. The paper presents work on bentonites modified with inorganic Na+ and organic HDTMA(+) (hexaclecyltrimethylammonium) cations and treated by 1.5, 3, 4.5 and 6M H2SO4. The characterization was based on the assignment of the stretching (nu) and bending (delta) vibrations observed in the MIR region and the first overtone [2 nu(R-H)] and combination [nu(R-H)+delta(R-H)] modes of R-H groups (R=O, C) in the NIR region. NIR spectrum shows the characteristic OH and CH bonds for organomontmorillonite. The effect of larger alkylammonium cations on the vibrations of Si-O and OH bonds in montmorillonite layers is observed. A few key-bands in the NIR region show the change of water in the interlayer montmorillonite. The intensities of the overtone (7080 and 6840cm(-1)) and combination (5242cm(-1)) bands of H2O have considerably decreased as a result of hydrophobic character of the NaOM. Spectra of acid-treated samples show a gradual decrease in the intensities of the OH overtone (near 7100-7000cm(-1)) and combination bands (4600-4300cm(-1)) reflecting a fewer number of octahedral atoms. This paper also points out that ATR technique and the 2nd derivative spectrum enables much precise band assignment

Examination of the influence of phenyltrimethylammonium chloride (PTMA) concentration on acetochlor adsorption by modified montmorillonite

The results presented in this paper show an impact of the concentration of the aromatic organic cation on the adsorption of acetochlor on the surface of the organic-modified montmorillonite. Natural montmorillonite from Bogovina (Boljevac municipality, Serbia) was used for organic modification in this experiment. Cation exchange capacity of this montmorillonite (86mmol 100g(-1) of clay) was determined using the methylene blue method. In pretreatment, montmorillonite was modified with NaCl. For the purpose of organic modification, three different concentrations of phenyltrimethylammonium chloride (PTMA) have been selected, based on calculated CEC value: 43mmol 100g(-1) of clay (0.5 CEC), 86mmol 100g(-1) of clay (1 CEC) and 129mmol 100g(-1) of clay (1.5 CEC). The changes in the properties of the inorganic and organic modified montmorillonite were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and batch equilibrium method. Freundlich coefficients show higher uptake of the herbicide by montmorillonite modified with PTMA, compared to inorganic-modified montmorillonite. The results also indicate the influence of the organic cation concentration on the adsorption of the selected herbicide

Adsorption of Acetochlor Herbicide on Inorganic- and Organic-Modified Bentonite Monitored by Mid-Infrared Spectroscopy and Batch Adsorption

The results of sorption of acetochlor herbicide with different concentrations (1-15 mu g/mL) in inorganic- and organic-modified bentonite are presented. Acetochlor sorption in both bentonite types was studied by attenuated total reflectance spectroscopy in the mid-infrared region and by batch equilibrium method. Infrared spectroscopy results suggest that the interaction of acetochlor with inorganic (or organic) bentonite takes place by mechanism involving the carbonyl stretching vibration and phenyl ring in the acetochlor molecule. The increase of the acetochlor concentration results in red shift of both corresponding band wavenumbers. Batch adsorption study pointed out more expressed sorption of acetochlor in organic bentonite

NIR and MIR spectroscopic characteristics of hydrophilic and hydrophobic bentonite treated with sulphuric acid

Near-infrared (NIR) and mid-infrared (MIR) spectroscopy are irreplaceable methods for characterization of bentonites. The paper presents work on bentonites modified with inorganic Na+ and organic HDTMA(+) (hexaclecyltrimethylammonium) cations and treated by 1.5, 3, 4.5 and 6M H2SO4. The characterization was based on the assignment of the stretching (nu) and bending (delta) vibrations observed in the MIR region and the first overtone [2 nu(R-H)] and combination [nu(R-H)+delta(R-H)] modes of R-H groups (R=O, C) in the NIR region. NIR spectrum shows the characteristic OH and CH bonds for organomontmorillonite. The effect of larger alkylammonium cations on the vibrations of Si-O and OH bonds in montmorillonite layers is observed. A few key-bands in the NIR region show the change of water in the interlayer montmorillonite. The intensities of the overtone (7080 and 6840cm(-1)) and combination (5242cm(-1)) bands of H2O have considerably decreased as a result of hydrophobic character of the NaOM. Spectra of acid-treated samples show a gradual decrease in the intensities of the OH overtone (near 7100-7000cm(-1)) and combination bands (4600-4300cm(-1)) reflecting a fewer number of octahedral atoms. This paper also points out that ATR technique and the 2nd derivative spectrum enables much precise band assignment

Influence of the organic complex concentration on adsorption of herbicide in organic modified montmorillonite

This study was undertaken to determine the impact of the organic complex concentration on the adsorption of herbicide (acetochlor) at the surface of the organic modified montmorillonite. In this work, natural montmorillonite from Bogovina (Boljevac municipality, Serbia) was used for organic modification. Cation-exchange capacity of this montmorillonite was determined using a methylene blue method (86mmol/100g of clay). Montmorillonite has been modified first with NaCl and then with hexadecyltrimethylammonium bromide (HDTMA-bromide) organic complex. Saturation of cation exchange capacity (CEC) was 50%, 100%, and 150%. Changes in the properties of the inorganic and organic montmorillonite have been examined using the X-ray diffraction, Fourier transform infrared spectroscopy, and batch equilibrium method. Montmorillonite modified with HDTMA-bromide demonstrated higher uptake of the herbicide, compared to the inorganic montmorillonite. Comparing the values Freundlich coefficients in batch equilibrium method, it can be seen that the adsorption of acetochlor decreased in the series: 0.5 CEC HM > 1 CEC HM > 1.5 CEC HM > NaM

SINTEZA I SPEKTROSKOPSKA KARAKTERIZACIJA NOVOG RASTVORA U ČVRSTOM STANJU KOJI SADRŽI Mg(II) I Cu(II) KOMPLEKSE SA HEKSADENTATNIM 1,3-PROPANDIAMIN-N,N,N’,N’-TETRAACETATO (1,3-PDTA) LIGANDOM: IN VITRO ANTIFUNGALNA AKTIVNOST 1,3-PDTA-Cu(II) KOMPLEKSA

New solid solution containing Mg(II) and Cu(II) complexes with hexadentate 1,3-propanediamine-N,N,N’,N’-tetraacetate ligand (1,3-pdta), [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O was synthesized and structurally characterized by elemental microanalyses, molar conductivity and spectroscopic (IR and UV-Vis) measurements. The spectroscopic data of [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O were compared with those for [Mg(H2O)6][Cu(1,3-pdta)].2H2O  complex of the known molecular structure determined by single-crystal X-ray diffraction analysis (Rychlewska et al., 2000). In vitro growth inhibition activity of [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O and [Mg(H2O)6][Cu(1,3-pdta)].2H2O against Colletotrichum acutatum and their effects on this fungus sporulation level are investigated. The obtained results showed that the highest percentage of inhibition for mycelium growth was achieved at a concentration of 500 µg/mL for the investigated complexes. The biological activities of the investigated complexes were compared with those for the commercial formulation of fungicide captan (Method 480 SC). Opisana je sinteza i spektroskopska karakterizacija (IR i elektronski apsorpcioni spektri) novog rastvora u čvrstom stanju koji sadrži Mg(II) i Cu(II) komplekse sa 1,3-propandiamin-N,N,N',N'-tetraacetato (1,3-pdta) ligandom, [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O. Spektroskopski podaci za [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O kompleks su upoređeni sa odgovarajućim podacima za [Mg(H2O)6][Cu(1,3-pdta)].2H2O kompleks poznate kristalne strukture. Ispitivana je in vitro antimikrobna aktivnost [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O i [Mg(H2O)6][Cu(1,3-pdta)].2H2O kompleksa prema fitopatogenoj gljivi Colletotrichum acutatum, koja uzrokuje antraknozu. Analiziran je uticaj različitih koncentracija [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O i [Mg(H2O)6][Cu(1,3-pdta)].2H2O kompleksa na rast micelija i na intenzitet sporulacije gljive. Dobijeni rezultati su pokazali da ovi kompleksi imaju najveću aktivnost pri koncentraciji od 500 µg/mL. Biološka aktivnost [Mg(H2O)6][Mg0.5Cu0.5(1,3-pdta)].2H2O i [Mg(H2O)6][Cu(1,3-pdta)].2H2O je upoređena sa odgovarajućom aktivnošću komercijalnog fungicida 480 SC (Kaptan)

Structural characterization and antimicrobial evaluation of chromium(III) and cobalt(III) complexes with 2,2-diMe-1,3-pdta: Tuning dimensionality of coordination polymer and the water content by alkyl substitution

Hexadentate 2,2-dimethyl-1,3-propanediamine-N,N,N',N'-tetraacetate (2,2-diMe-1,3-pdta) ligand, containing two methyl substituents at the central carbon atom of a 1,3-propanediamine, has been prepared and used for the synthesis of Na[Cr(2,2-diMe-1,3-pdta)].3.75H2O (1) and Na[Co(2,2-diMe-1,3-pdta)].3.88H(2)O (2) complexes. These complexes were characterized by IR and electronic absorption spectroscopy, and single-crystal X-ray diffraction analysis. NMR (H-1 and C-13) spectroscopy was additionally applied for the characterization of complex 2. Crystallographic data indicate that the two investigated crystals are isostructural and contain 2,2-diMe-1,3-pdta ligand coordinated to metal ion through 2N and 4O atoms forming an octahedral complex in which the six-membered 1,3-propanediamine chelate ring adopts a twist-boat conformation. There are four such complex anions in the symmetry independent part of the unit cell. Each complex anion is further connected to the sodium counterion(s) via the bridging carboxylate group(s). Structural changes in 2,2-diMe-1,3-pdta-Cr(III) complex stimulated solely by the presence of alkyl side groups are discussed. The present study shows that in 1,3-pdtatype complexes of Cr(III) and Co(III), the environment at coordination centre can be modified by introducing substitution in one of the carbon atoms of the diamine and the resulting difference in the subunit structure can bring about noticeable change in molecular and crystal structure. The examples illustrate the importance of the steric effect for the fine tuning of the dimensionality of the resulting coordination polymer and the water content. The antimicrobial activity of complexes 1 and 2 was evaluated against different bacterial and Candida spp., while their cytotoxic effects were tested on the normal human lung fibroblast cell line (MRC-5)