A series of novel Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes with oxaprozin (Hoxa), a non-steroidal anti-inflammatory drug, has been synthesized. The drug and complexes have been ...characterized by elemental and thermogravimetric (TG) analysis, Fourier transform (FT)-IR, 1H-NMR, 13C-NMR, UV-Vis spectroscopy and magnetic susceptibility measurements. The (pseudo)octahedral geometry has been proposed for all complexes based on electronic spectra and magnetic moments. With exception of the Cu(II) complex, where bridging bidentate mode of COO groups has been found, FT-IR spectra confirmed chelately coordinated COO groups in the other complexes. The general formula of the complexes is M(H2O)2(oxa)2·xH2O, with x=2 for M=Mn, Co and Ni and x=1.5 for Zn. The binuclear Cu(II) complex, Cu2(H2O)2(OH)(oxa)3·2H2O, has strong Cu-Cu interactions of antiferromagnetic type. The complexes and Hoxa did not exhibit the cytotoxic effect to peritoneal macrophages. For the first time these complexes have been tested for their in vitro antiproliferative activity against human colon and breast cancer cell lines, HCT-116 and MDA-231, respectively. For all investigated compounds significant antiproliferative effects have been observed. Ni(II) complex has been shown to be a promising antiproliferative agent exerting excellent activity against HCT-116 even in nanomolar concentrations.
•Degradation of two polymeric phthalatocuprate(II) dihydrates was studied using TG/DSC/MS measurements and XRPD analysis.•The reversibility of dehydration processes was identified using XRPD and ...TG/DSC analysis.•Detail analysis of dehydration kinetics was studied using isoconversional and non-isoconversional methods.•Thermodynamic and kinetic parameters for dehydration process have been determined.•The dehydrated complexes were investigated as possible candidates for H2 adsorption, using molecular simulations.
Thermal dehydration of two heterometallic complexes containing dianion of phthalic acid, pht, Na2Cu(pht)2·2H2O, 1, and K2Cu(pht)2·2H2O, 2, was investigated under non-isothermal conditions. Mechanism and kinetics of dehydration were analyzed in detail using TG/DSC/MS measurements, XRPD analysis and FT-IR spectroscopy. The reversibility of dehydration processes was identified. According to XRPD, dehydrated product of 1 maintains original structure, but dehydration of 2 undergoes structural transformation giving a dehydrated product of different crystal structure. In both cases dehydration process involves more than one elementary step, which was confirmed using isoconversional methods Deconvolution of this process using Fraiser-Suzuki function yielded two single step processes for 1 and 2. Subsequent kinetic analysis was performed using Màlek algorithm, resulting in the determination of kinetic triplets (Ea, A and f(α)) for each individual step. In addition, the dehydrated complexes were investigated as possible candidates for H2 adsorption, using molecular simulations.
Two new isostructural M(II) (M = Ni, Co) complexes with 2,2'-dipyridylamine (dipya) and dianion of terephthalic acid (H2tpht), M(dipya)2(H2O)2(tpht) ∙ 2H2O, have been synthesized by ligand exchange ...reaction and characterized by single-crystal X-ray diffraction, FTIR spectroscopy, TG/DSC analysis and magnetic measurements. The crystal structures of M(dipya)2(H2O)2(tpht) ∙ 2H2O consist of discrete complex units in which M(II) adopts deformed octahedral geometries. Two dipya ligands and two water molecules are coordinated to M(II) atom, tpht acts as a counter ion, while additional two water molecules remained uncoordinated. By numerous hydrogen bonds, all structural fragments are connected in three different chains which extend along 100, 010 and 001 directions, giving as a result a complex 3D network. The stabilization of 3D structure is accomplished by non-covalent face to face π-π interactions among pyridyl ring of dipya and benzene ring of tpht from adjacent chains. Towards the applied magnetic field, the both complexes exhibited almost perfect paramagnetic behavior.
A series of six novel 2-(5-arylidene-2,4-dioxotetrahydrothiazole-3-yl)propanoic acids and six corresponding methyl esters were synthesized. All compounds were characterized by melting points, ...elemental analysis, FT-IR, 1H and 13C NMR spectroscopy. Crystal structure of methyl-2-(5-(4-methoxybenzylidene)-2,4--dioxotetrahydrothiazole-3-yl)propionate was confirmed by X-ray analysis. The antiproliferative activity of all synthesized compounds against human colon cancer, breast cancer and myelogenous leukemia cell lines, i.e. HCT-116, MDA-231 and K562, respectively, was evaluated. The results indicate that antiproliferative activity of the synthesized esters is better than the activity of the corresponding acids. All synthesized compounds showed significant antiproliferative effects against HCT116 cells in all tested concentrations (0.01–100μM). Moreover, in vitro antimicrobial activity against a wide range of tested microorganisms was examined.
A new Bi-rich part of Bi2O3?PbO phase diagram was determined using differential thermal analysis and X-ray powder diffraction techniques. Four solid solutions, ?-Bi2O3, ?-Bi2O3, ?-Bi2O3 and ...?ss-Bi8Pb5O17, can be distinguished below 37.5 mol % of PbO and one compound, ?2-Bi8Pb5O17. Two of them, ?-Bi2O3 and ?ss-Bi8Pb5O17 are high-temperature phases. The large field of ?-Bi2O3 stability was implemented making the crucial difference comparing to phase diagrams from the Bi2O3?PbO system published so far.
In search of novel photoactive liquid crystals, we have synthesized a series of five-ring pyridine-based bent-core compounds bearing different substituents at the peripheral phenyl rings (CH 3 O, Cl ...and NO 2 ). Their mesomorphic behaviour has been investigated by polarizing optical microscopy, differential scanning calorimetry and X-ray scattering, and then compared with the unsubstituted parent compound. The introduction of the methoxy groups at the peripheral phenyl rings of the bent core results in a non-mesomorphic compound, whereas the chloro- and nitro-substituted compounds form enantiotropic B1-like phases. Significant changes in the textures and transition temperatures of the mesophase have been observed under UV light. The present investigation of the mesomorphic properties of the synthesized compounds, coupled with the analysis of the molecular packing of the related three-ring compounds, will help design self-organized molecules suitable for UV indicators.
In this work, Zn(CH3COO)2 ? 2H2O with AgNO3 content from 0 to 6mol% was
solvothermally treated at 120?C for 18 h in the presence of poly(vinyl
pyrrolidone), ethylene glycol and sodium hydroxide. The ...structural,
microstructural and photocatalytic properties of the unmodified and Ag
modified ZnO powders have been investigated by the XRPD, FESEM, TEM, UV-vis,
Raman and BET techniques. The Ag modified samples consist of ZnO nanocrystals
and metallic Ag on the surface. The average crystallite size of all samples
was about 20 nm. The FESEM revealed the uniformity in size and approximately
spherical shape of ZnO nanoparticles. The BET data suggest that all prepared
samples are mesoporous. All prepared samples showed higher photocatalytic
efficiency in the degradation of the Reactive Orange 16 (RO16) azo dye than
the commercial ZnO. In addition, Ag modified ZnO powders, especially those
with 1.5 and 0.75mol%of Ag, were more efficient than the unmodified one.
A terephthalate-bridged heteronuclear Cu(II)?Mn(II) complex Cu2Mn(dipya)2(tpht)3n, I, where dipya is 2,2?-dipyridylamine and tpht is the anion of 1,4-benzenedicarboxylic (terephthalic, H2tpht) acid ...was synthesized under hydrothermal conditions. The obtained complex I was characterized by a single-crystal X-ray diffraction, FTIR spectroscopy, TG/DSC analysis and magnetic measurements. The Cu(II) and Mn(II) metal centers adopt distorted octahedral geometry and they are linked by bridging tpht ligands. Two crystallographically different tpht anions are coordinated as tridentate and hexadentate ligands forming two-dimensional layers. The layers are interconnected by hydrogen bonds and additionally stabilized by non-covalent C?H??? interactions. The measurements of magnetic susceptibility proved that I is an almost perfect paramagnet.
The title compound, (Hdipya)(H3pyr), where Hdipya is protonated
2,2?-dipyridilamine and H3pyr is monoanion of pyromellytic acid (H4pyr), was
obtained from the reaction mixture containing Zn(II) ions, ...dipya, Na4pyr
(the molar ratio 2 : 2 : 1) and HNO3. The products (micro- and
single-crystalline) were characterized by X-ray structure determination,
FT-IR spectroscopy and TG/DSC analysis. The most striking structural feature
of (Hdipya)(H3pyr) are short inter- and extremely short intramolecular
hydrogen bonds. These bonds mutually connect cations and anions making thin
layers parallel to the crystallographic (223) plane. Also, quite unusual,
linear proton-bound polymeric {H(H2pyr)-}n anions were identified in the
structure. The results of crystal structure determination are compared with
FT-IR and TG/DSC data. The low position of nas(COO) vibration at 1660 cm-1
is in accordance with strong hydrogen bonding. This value can be used as a
measure of C=O bond order, which is calculated to be 1.81.