Liliana Mazur

Synthesis, structure elucidation and antitumour activity of N-substituted amides of 3-(3-ethylthio-1,2,4-triazol-5-yl)propenoic acid.

New N-substituted amides of 3-(3-ethylthio-1,2,4-triazol-5-yl)propenoic acid (2-12) were designed and prepared by the condensation reaction of exo-S-ethyl-7-oxabicyclo-[2.2.1]-hept-5-ene-2,3-dicarbonyl isothiosemicarbazide (1) with primary amines. The chemical structure of all compounds was confirmed by IR, (1)H NMR, (13)C NMR spectra, the X-ray crystallography (for compounds 8, 11, 12) and elemental analysis. Moreover, compounds 9-11 were screened for their anticancer activity. Compounds 9 (in concentrations of 0.32 mM and 0.16 mM), 10 (in concentrations of 0.28 mM and 0.14 mM), and 11 (in concentrations of 0.35 mM and 0.17 mM) were found to be evidently effective in vitro against lung cell line (IC50). The distinctly marked antiproliferative effect of compounds 9 and 10 in breast carcinoma cells in vitro was ascertained. Moreover, the lowest cytotoxicity of compound 9 in concentrations of 0.16 mM and 0.03 mM against the normal skin fibroblast cell line and breast carcinoma cell in vitro after 24- and 48-h periods of incubation was noticed in this study.

Synthesis, crystal structure and biological activities of a novel amidrazone derivative and its copper(II) complex — A potential antitumor drug

A new linear amidrazone derivative, 6-acetyl-cyclohex-3-enecarboxylic acid [1-pyridin-2-yl-1-(pyridyn-2-yloamin)meth-(Z)-ylidene] hydrazide, H(2)L (2) and its Cu(II) complex, [Cu(2)L(2)]·4H(2)O (3) were synthesized and characterized by elemental analysis, IR and (1)H NMR spectroscopy and cyclic voltammetry. Compound 2 was synthesized in the equimolar reaction of N(3)-substituted amidrazone with cis-1,2,3,6-tetrahydrophthalic anhydride. The Cu complex of 2 was obtained in the reaction with copper(II) acetate. The molecular structures of 2 and 3 were determined by X-ray crystallography. The parent ligand exists in its amide-hydrazone form in the solid state. The central amidrazone moiety has a Z configuration with respect to the double C=N bond. Coordination to the metal center promotes Z/E isomerization of the hydrazone group of the ligand. Compound 3 is a dinuclear four-coordinated Cu(II) complex with the amidrazone ligand behaving as a tetradentate double deprotonated chelating one. Several biological activities of 2 and 3 were examined in vitro; they were: antimicrobial properties against selected bacterial and fungal strains, suppression of phytohemagglutinin A (PHA)-induced proliferation of human peripheral blood mononuclear cells (PBMC) and their effects on tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) production. The cytotoxic activity of Cu(II) complex was determined with respect to the four carcinoma cell lines (SW 984, CX-1, L-1210, A-431). The studied complex exhibited significant cytotoxic effects (particularly against CX-1 colon carcinoma), comparable to those reported for cisplatin. Both compounds have shown a relatively low antibacterial activity and were devoid of antifungal properties.

Synthesis, crystal structure, spectroscopic properties, and antimicrobial studies of a zinc(II) complex of p-coumaric acid

The synthesis of the zinc(II) complex of p-coumaric acid is described. The chemical formula of the complex as obtained from the single-crystal X-ray analysis is [Zn4(C9H7O3)8(H2O)6]·4(H2O). The compound crystallizes in the triclinic space group P-1 with one molecule in the unit cell. There are two crystallographically independent Zn(II) cations in the structure. Zn1 is six-coordinate to three different carboxylate oxygens and three waters in a distorted octahedral geometry, whereas Zn2 ions are connected to four oxygens from four p-coumarate anions resulting in tetrahedral geometry. Adjacent cations are connected by bridging carboxylates to form centrosymmetric tetranuclear aggregates. Adjacent molecules are connected by a net of strong O–H O hydrogen bonds into a 3D supramolecular framework with 1D open channels filled with water molecules. The zinc complex was characterized by infrared spectroscopy and 1H and 13C NMR spectra. The antimicrobial activities of zinc p-coumarate toward Bacillus subtilis, Candida albicans, Pseudomonas aeruginosa, Proteus vulgaris, and Staphylococcus aureus were tested.

2-[4-Phenyl-5-(2-pyridyl)-4H-1,2,4-triazol-3-yl]nicotinic acid: a case of solvent-dependent polymorphism

The title compound, C(19)H(13)N(5)O(2), crystallizes in two monoclinic forms depending on the solvent used. From methanol or acetone, a yellow form [(Ia), m.p. 533 K] in the space group P2(1) is obtained, while with ethanol as the solvent, an orange form [(Ib), m.p. 541 K] in the space group Cc results. The conformers observed in the two polymorphs differ primarily in the relative orientation of pyridine/phenyl and triazole rings. Molecules of both polymorphs form chains through carboxyl O-H...N hydrogen bonding; however, in each crystal structure, a different group acts as acceptor, viz. a triazole and a pyridyl N atom for (Ia) and (Ib), respectively. This is the first case of polymorphism observed for crystals of a 3,4,5-trisubstituted 1,2,4-triazole derivative.

Crystal structure, spectroscopic and thermal studies of 3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid sodium salt

The crystal structure, infrared spectrum and thermal stability of 3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid sodium salt have been studied. The compound of general formula {[Na2L2 · 3H2O] · H2O} n is a two-dimensional polymer, in which Na ions are bridged by one or two water molecules and additionally coordinated to oxygen atoms of carboxylate, hydroxy and methoxy groups. The structure is stabilized by a hydrogen bond network. The compound dehydrates at 75°C and then decomposes at 150°C. The IR spectra of the salt and free acid are discussed.

Synthesis, crystal structure, spectroscopic and thermal investigations of neodymium(III) biphenyl-4,4′-dicarboxylate framework

AbstractThe three-dimensional complex {[Nd(bpdc)1.5(DMF)]·1.4DMF}n (DMF=N,N′-dimethylformamide, bpdc=biphenyl-4,4′-dicarboxylate) was synthesized using the solvothermal method. The crystal structure of the neodymium(III) complex has been determined by single-crystal X-ray diffraction method at 100(2) K. The polymeric structure consists of neodymium polyhedra bridged by bpdc ligands. Eight-coordinated Nd(III) atoms are surrounded by seven oxygen atoms from six bpdc moieties and one oxygen atom from the DMF molecule. The 3D structure of the complex contains two types of channels occupied by DMF molecules. Thermal analysis revealed that DMF molecules are lost in a stepwise manner. The infrared spectrum confirmed full deprotonation of acid and presence of DMF molecules in the structure.

Co-crystal formation between 2-amino-4,6-dimethylpyrimidine and new p-xylylene-bis(thioacetic) acid

Novel p-xylylene-bis(thioacetic) acid (p-XBTA) and its co-crystals with 2-amino-4,6-dimethylpyrimidine (DMP) have been synthesized and characterized by single-crystal X-ray diffraction, infrared spectroscopy and thermal analysis methods (TG/DSC). Depending on the crystallization conditions, three different multicomponent crystal forms have been isolated with various chemical compositions and stoichiometries of the co-formers. The ATR-FTIR spectra of the co-crystals display the stretching vibration bands for the co-formers with associated shifts confirming the formation of new phases. DSC and TG were used to reveal the relative stabilities of new solids compared to those of the co-formers.

Calcium complex of 2,5-dihydroxybenzoic acid (gentisic acid): synthesis, crystal structure, and spectroscopic properties

Abstract The synthesis, crystal structure, and spectral characteristics (IR, Raman, and 1H and 13C NMR) of a monomeric hexa(aqua)calcium compound, viz. [Ca(C7H5O4)2(H2O)6]·H2O (C7H5O4 = 2,5-dihydroxybenzoate), are reported. The central Ca(II) located on a twofold axis is eight coordinate in an approximate square antiprismatic environment, bonded to two monodentate 2,5-dihydroxybenzoate ligands via the carboxylate oxygen, and six waters. The adjacent monomeric units are linked with the aid of several O–H⋯O hydrogen bonds.

Crystal structure, spectroscopic and thermal studies of anhydrous potassium 2,6-dihydroxybenzoate

The crystal structure, infrared spectrum and thermal stability of the potassium salt of 2,6-dihydroxybenzoic acid have been studied. The compound crystallizes in the monoclinic space group P21/n with a = 3.847(1) Å, b = 15.099(5) Å, c = 13.248(4) Å, β = 98.35(2)° and Z = 4. The compound of the general formula KL is a three-dimensional polymer, in which K ions are bridged by coordinated organic ligands by oxygen atoms of carboxylate and hydroxy groups. The anhydrous compound decomposes at 230°C. The IR spectrum of the potassium salt is discussed.

Synthesis and evaluation of new amidrazone-derived hydrazides as a potential anti-inflammatory agents

The series of new hydrazide derivatives were synthesized in reactions of N3-substituted amidrazones with cyclic anhydrides as potential anti-inflammatory and antibacterial agents. The compounds were characterized by 1H-13C two-dimensional NMR techniques, which revealed the presence of two tautomeric forms in DMSO-d6 solutions, while the molecular structure of one species was confirmed by single-crystal X-ray diffraction. The anti-inflammatory effects of hydrazides on peripheral blood mononuclear cells were experimentally evaluated. Three compounds showed antiproliferative activity comparable to ibuprofen. One derivative demonstrated strong reduction of lymphocyte proliferation stimulated by anti-CD3 antibody (by 90%) and PHA, as well as low cell toxicity. The obtained compounds exhibited relatively weak antibacterial activity; they were more effective against Gram-positive bacterial strains.Graphical abstract