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Publisher Copyright: © 2023 The Authors A series of quaternary ammonium fluoroquinolones was obtained by exhaustive methylation of the amine groups present at the 7-position of fluoroquinolones, including ciprofloxacin, enoxacin, gatifloxacin, lomefloxacin, and norfloxacin. The synthesized molecules were tested for their antibacterial and antibiofilm activities against Gram-positive and Gram-negative human pathogens, i.e. Staphylococcus aureus and Pseudomonas aeruginosa. The study showed that the synthesized compounds are potent antibacterial agents (MIC values at the lowest 6.25 μM) with low cytotoxicity in vitro as assessed on the BALB 3T3 mouse embryo cell line. Further experiments proved that the tested derivatives are able to bind to the DNA gyrase and topoisomerase IV active sites in a fluoroquinolone-characteristic manner. The most active quaternary ammonium fluoroquinolones, in contrast to ciprofloxacin, reduce the total biomass of P. aeruginosa ATCC 15442 biofilm in post-exposure experiments. The latter effect may be due to the dual mechanism of action of the quaternary fluoroquinolones, which also involves disruption of bacterial cell membranes. IAM-HPLC chromatographic experiments with immobilized artificial membranes (phospholipids) showed that the most active compounds were those with moderate lipophilicity and containing a cyclopropyl group at the N1 nitrogen atom in the fluoroquinolone core.

Syntheses of two new monomers, namely the glucose derivatives 2,3,4,6-tetra-O-acetyl-1 methacryloyl-glucopyranose (MGlc) and 2,3,4,6 tetra-O-acetyl-1-acryloylglucopyranose (AGlc), are presented. Their chemical structures were determined by the FTIR, 1H and 13C NMR spectroscopies, the single-crystal X-ray analysis, supported by the powder X-ray diffraction, and the DSC analyses. Molecules of both monomers exist in the β-anomeric form in the solid state. The variable temperature X-ray diffraction studies, supported by the DSC analyses, revealed AGlc’s propensity for polymorphism and temperature-induced phase transitions. MGlc and AGlc crystallised from methanol were polymerized or copolymerized with methyl methacrylate and N-vinylpyrrolidone. The biodegradabilities of polymers as well as thermal and optical properties were studied. The results show that some properties of the obtained homopolymers and copolymers resemble those of PMMA. The main difference is that the AGlc and MGlc homopolymers are biodegradable while PMMA is not. The ternary copolymers, i.e., MGlc/AGlc-MMA-NVP lose more than 10% of their weight after six months.

We present a crystallographic and computational study of three hydantoin-based active pharmaceutical ingredients nitrofurantoin, furazidin, and dantrolene aimed at identifying factors resulting in different propensities of these compounds to form polymorphs, hydrates, solvates, and solvate hydrates. This study is a continuation of our research towards understanding how small structural differences in closely related compounds affect their propensity to form different crystal phases, as all three compounds contain an imidazolidine-2,4-dione scaffold and a N-acyl hydrazone moiety and all form multiple crystalline phases. Crystallographic and computational analysis of the already known and newly obtained nitrofurantoin, furazidin and dantrolene crystal structures was performed by dissecting the properties of individual molecules and searching for the differences in tendency to form hydrogen bonding patterns and characteristic packing features. The propensity to form solvates was found to correlate with the relative packing efficiency of neat polymorphs and solvates and the ability of molecules to pack efficiently in several different ways. Additionally, the differences in propensity to form solvate-hydrates were attributed to the different stability of the hydrate phases.

Two coordination polymers, [Co(µ4-L)(H2O)2]n (1) and [Ni(µ-L)(H2O)4]n (2), were solvothermally assembled from the corresponding metal(II) chlorides and biphenyl-4,4-dioxydiacetic acid (H2L) as a flexible dicarboxylate linker. The cobalt(II) compound 1 featured a layer-pillared 3D metal-organic network with a cds topology, while the nickel(II) derivative 2 represented a linear chain 1D coordination polymer with a 2C1 topology. The µ4− and µ-L2− linkers exhibited different denticity and coordination modes in the synthesized compounds, thus contributing to their structural diversity. The dimensionality of 1 and 2 had an influence on their thermal stability and decomposition processes, which were investigated in detail by TG-DSC and TG-FTIR methods. Thermal decomposition products of coordination polymers were also analyzed by PXRD, confirming the formation of Co3O4/CoO and NiO as final materials. The obtained compounds broaden a family of coordination polymers assembled from flexible dicarboxylate linkers.

A highly efficient synthesis of new chiral bisphosphanes derived from the renowned NORPHOS ligand is presented. The synthesis involves ring-opening metathesis of NORPHOS dioxide with an external olefin, followed by saturation of the new double bonds and adjustment of the oxidation level of phosphorus centers oxidation level. The synthesized bisphosphanes retain the configuration and enantiomeric purity of the starting NORPHOS. Their utility as ligands in asymmetric catalysis is exemplified using an open-NORPHOS ligand in some benchmark Rh-catalyzed hydrogenations of enamides where excellent chemical yields and enantiomeric purities of the products have been secured. The proposed protocol demonstrated the possibility of a straightforward synthesis of new chiral catalysts to be utilized in the asymmetric synthesis of pharmaceutically important compounds, such as amino acid derivatives.

A multifunctional, biologically active hydrazone compound (BZH) has been cocrystallized with four aliphatic dicarboxylic acids of different carbon linkage. Multiple hydrogen-bond donor and acceptor...

A new Au(III) complex was synthesized from an amidrazone derivative and HAuCl4. Cyclization of amidrazone moiety lead to the 1,2,4-triazolo[1,5a]pyridine ring system, followed by Au(III) chelation. The crystal and molecular structure of the final compound was studied by single crystal X-ray diffraction as well as by 1H 13C and 1H 15N HMQC- and HMBC-NMR spectroscopy, which resulted in the assignment of all detected signals. This species was tested in vitro as an antibacterial and antiproliferative agent. It exhibited good antibacterial activity against Staphylococcus aureus and was proved to be more potent than amoxicillin against Bacillus subtilis and the drug resistant strain of Klebsiella pneumoniae. In contrast, its antiproliferative properties against cancer cell lines A549, HT-29, MV-4-11 and MCF-7 were relatively low.

The thermal properties of nine biologically important fused azaisocytosine-containing congeners, e.g. 3-(thiophen-2-yl)-8-(R-phenyl)-7,8-dihydroimidazo[2,1-c][1,2,4]triazin-4(6H)-ones (1-9), were studied by means of different thermal analysis methods (TG-DTG-DSC and TG-FTIR). The influence of heating atmosphere (air and nitrogen) on the pathways of thermal decomposition was investigated. The thermal stability of the investigated compounds in air can be ordered (in relation to the substituent attached at the phenyl moiety and denoted as R) as follows: 2-CH3O

A new series of four coordination polymers of alkali metals (Li, Na, and K) was assembled from a poorly explored building block, biphenyl-4,4′-dioxydiacetic acid (H2L), and characterized by FTIR-ATR, TG-DSC, elemental analysis, and single crystal X-ray diffraction methods. The obtained structures range from 2D coordination polymers [Li2(µ-L)(µ-H2O)2(H2O)2] (1) and [Na2(µ4-L)(µ-H2O)2(H2O)2] (2) to 3D metal-organic frameworks [Na2(µ6-L)(µ-H2O)2] (3) and [K2(µ10-L)] (4). The influence of metal ionic radii on the crystal structures of the coordination polymers and conformation of the flexible biphenyl-4,4′-dioxydiacetate ligand was analyzed. Structural complexity increases within the series of products 1–4 following the Li

A series of new linear trisubstituted N1-acylamidrazones have been investigated using a variety of analytical techniques and theoretical calculations to check the influence of the type of N1-acyl substituent on the resonance forms and conformational behavior in the solid state and in solution. The 1D- and 2D-NMR experiments, supported by computational studies, revealed that in solution all amidrazones exhibit conformational syn/anti isomerism that results from the hindered rotation around the amide bond. In the case of the propenoic acid derivative, the ROESY, HSQC, and HMBC experiments proved a third equilibrium structure that corresponds to the planar ylide form. The SC XRD data confirmed that the compounds tend to exist as Z-anti conformers of their hydrazone-amide tautomeric species in the solid state. The carboxyl-amide heterosynthon is favoured provided that the carboxyl group is not involved in the intramolecular hydrogen bonding. Interestingly, after replacement of the cyclic C1-substituent by the smaller propanoic acid unit, which results in lower steric hindrance, both syn and anti conformers can exist. Furthermore, in the former case both the neutral molecules and zwitterions are present in the single crystal. The relative stability of the distinct crystal forms was examined using TG-DSC methods supplemented with cohesive energy calculations (CRYSTAL). The results indicate that the unsolvated forms are stable in a wide range of temperatures; however, inclusion of solvent molecules makes them prone to cyclization at higher temperatures. This paper reports the first observation of temperature-induced cyclization of N1-acylamidrazone to its cyclic triazole derivative in the solid state.

The Mg(II) and heterometallic Mn(II)/Na(I) complexes of isoferulic acid (3-hydroxy-4-methoxycinnamic acid, IFA) were synthesized and characterized by infrared spectroscopy FT-IR, FT-Raman, electronic absorption spectroscopy UV/VIS, and single-crystal X-ray diffraction. The reaction of MgCl2 with isoferulic acid in the aqueous solutions of NaOH resulted in synthesis of the complex salt of the general formula of [Mg(H2O)6]⋅(C10H9O4)2⋅6H2O. The crystal structure of this compound consists of discrete octahedral [Mg(H2O)6]2+ cations, isoferulic acid anions and solvent water molecules. The hydrated metal cations are arranged among the organic layers. The multiple hydrogen-bonding interactions established between the coordinated and lattice water molecules and the functional groups of the ligand stabilize the 3D architecture of the crystal. The use of MnCl2 instead of MgCl2 led to the formation of the Mn(II)/Na(I) complex of the general formula [Mn3Na2(C10H7O4)8(H2O)8]. The compound is a 3D coordination polymer composed of centrosymmetric pentanuclear subunits. The antioxidant activity of these compounds was evaluated by assays based on different antioxidant mechanisms of action, i.e., with •OH, DPPH• and ABTS•+ radicals as well as CUPRAC (cupric ions reducing power) and lipid peroxidation inhibition assays. The pro-oxidant property of compounds was measured as the rate of oxidation of Trolox. The Mg(II) and Mn(II)/Na(I) complexes with isoferulic acid showed higher antioxidant activity than ligand alone in DPPH (IFA, IC50 = 365.27 μM, Mg(II) IFA IC50 = 153.50 μM, Mn(II)/Na(I) IFA IC50 = 149.00 μM) and CUPRAC assays (IFA 40.92 μM of Trolox, Mg(II) IFA 87.93 μM and Mn(II)/Na(I) IFA 105.85 μM of Trolox, for compounds’ concentration 10 μM). Mg(II) IFA is a better scavenger of •OH than IFA and Mn(II)/Na(I) IFA complex. There was no distinct difference in ABTS•+ and lipid peroxidation assays between isoferulic acid and its Mg(II) complex, while Mn(II)/Na(I) complex showed lower activity than these compounds. The tested complexes displayed only slight antiproliferative activity tested in HaCaT human immortalized keratinocyte cell line within the solubility range. The Mn(II)/Na(I) IFA (16 μM in medium) caused an 87% (±5%) decrease in cell viability, the Mg salt caused a comparable, i.e., 87% (±4%) viability decrease in a concentration of 45 μM, while IFA caused this level of cell activity attenuation (87% ± 5%) at the concentration of 1582 μM (significant at α = 0.05).

Polymorphism of four biologically active 3-(4,5-diaryl-4H-1,2,4-triazole-3-yl)propenoic acid derivatives has been investigated. Traditional solution-based solid-state forms screening revealed three anhydrous forms of 3-[4-phenyl-5-(2-pyridyl)-4H-1,2,4-triazole-3-yl]propenoic acid. Noteworthy, two pairs of concomitant polymorphs were detected for this system. Two other compounds were found to be dimorphic. The molecular and crystal structures of all obtained crystal forms were established by single-crystal X-ray diffraction. The resulting crystal structures were analyzed in terms of molecular conformation, intermolecular interaction patterns, and crystal packing motifs. The experimental studies were supported by extended lattice and interaction energy calculations. It was found that the carboxylic group adopts the anti conformation in all studied forms and is involved in the intramolecular O–H···Ntriazole hydrogen bonding. In consequence, the association modes are dominated by the weak C–H···O, C–H···N hyd...

A straightforward synthesis of a sterically hindered and electron rich bidentate monophosphine biaryl ligand Sym-Phos of C,P-type of complexation was realised in a high yield starting from simple substrates in easily affordable conditions. In combination with a palladium source, the obtained ligand formed a highly active catalyst mediating sterically demanding Suzuki–Miyaura coupling reactions in aqueous media even at 60 °C and with no need to protect the reaction mixture by an inert gas.

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.

Synthesis, crystal structure, and thermal behavior studies of different solid-state forms of two new 2-pyridinecarboxaldehyde N-acylhydrazones are reported together with the corresponding computational analyses. Both compounds exist in two anhydrous polymorphic forms and crystallize also as hydrates. All of the studied crystals were obtained via solvent evaporation from solutions. Structural features were determined using single-crystal XRD (employing the transferred aspherical atom model, TAAM) supported by solid-state NMR. The relative stability of different crystal forms was examined experimentally using the TGA-DSC methods and supplemented with extended lattice and interaction energy calculations and crystal entropy estimation. The results confirmed the prevalent role of strong hydrogen bonds of N–H···O and N–H···N type in stabilization of anhydrous crystals. In the case of hydrates, water molecules incorporated into the crystal network are involved in the most efficient hydrogen bonds contributing si...

(Benzylthio)acetic acid (Hbta) was synthesized with 78% yield from benzyl chloride and thiourea as substrates. Well-shaped crystals of Hbta were grown by slow solvent evaporation technique from pure methanol. The compound was investigated by single-crystal X-ray and powder diffraction techniques and was also characterized by other analytical methods, like ATR-FTIR, 1H and 13C NMR and TG/DSC. The acid molecule adopts bent conformation in the solid state. The crystal structure of Hbta is stabilized by numerous intermolecular interactions, including O–H···O, C–H···O, C–H···S and C–H···π contacts. Thermal decomposition of the obtained material takes place above 150 °C.

A novel 4,4′-disubstituted biphenyl derivative featuring two acetic acid side arms symmetrically attached to a biphenyl system, that is biphenyl-4,4′-diacetic acid (H2bpda), has been successfully synthesized by means of the three-stage organic strategy. The synthesis product was characterized by elemental analysis, various spectroscopic techniques including FT-IR, Raman, 1H and 13C NMR as well as thermogravimetric and TG–FT-IR coupled measurements. The phase purity of material was verified on the basis of the X-ray powder diffraction. The studied compound crystallizes in the monoclinic P21/c space group with half of the molecule in the asymmetric unit. Structural studies indicate intermolecular O H⋯O hydrogen bonding between the carboxylic groups of the adjacent molecules of H2bpda. The occurrence of intermolecularly associated carboxylic groups can also be clearly seen in the vibrational spectra of the acid. On thermal analysis both in air and nitrogen an anhydrous compound demonstrates considerable thermal stability.

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.

The novel N-(substituted-thioureido)aminobicyclo dicarboximide and 3,4-disubstituted 1,2,4-triazolino-5-thione were synthesized and their antimicrobial and antituberculosis activities were examined. Selected dicarboxylic acid anhydrides were used to obtain derivatives of thiosemicarbazide and dicarboximide. Dicarboximides were also cyclized in the presence of an alkaline solution giving 1,2,4-triazolino-5-thione. The chemical structure of all compounds was confirmed by IR, 1H NMR, 13C NMR, the X-ray crystallography (6, 11) and elemental analysis. Antimicrobial and antituberculosis activities of the derivatives were measured.

The series of isostructural lanthanide coordination polymers with the empirical formula [Ln2(PDA)3(H2O)]·2H2O, where PDA = 1,4-phenylenediacetate anion = [C8H8(COO)2]2−; Ln = La-Lu(III), and Y(III) were produced in the reaction of LnCl3·nH2O with ammonium salt of 1,4-phenylenediacetic acid in water solution. The compounds were characterised structurally using powder X-ray diffraction, elemental and thermogravimetric analyses as well as FT-IR spectroscopy. Thermogravimetric analyses show that in the range 60–170 °C the dehydration process occurs. The thermal stability of dehydrated compounds, Ln2(PDA)3 increased from about 200–350 °C in the whole series of complexes. Single-crystal X-ray diffraction analysis for the Gd(III) complex revealed that the compound crystallizes in the monoclinic P21/c space group with a = 21.863(2) A, b = 10.035(1) A, c = 13.854(1) A, β = 91.53(1)° and V = 3,038.5(4) A3. The complex contains one-dimensional gadolinium-carboxylato chains, which are connected with the –CH2–C6H4–CH2– spacers of PDA ligand to the three-dimensional metal–organic framework.

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, Can...

The influence of synthesis conditions on the structural and thermal properties of solid lanthanide 1,2,3,4,5,6-benzenehexacarboxylates (mellitates) was investigated. The general formula of the complexes is Ln 2 (C 12 O 12 )· n H 2 O (where Ln = Nd(III) and Er(III), n = 10 for Nd, and n = 14 for Er – mild conditions; n = 6 for Nd and Er – hydrothermal synthesis). They were characterized by elemental analysis, X-ray diffraction methods, IR spectroscopy and thermal analysis methods (TG-DSC and TG-FTIR). The prepared complexes are crystalline but not isostructural. The IR spectra confirm deprotonation of all carboxylic groups in all investigated complexes. Their thermal stability as well as pathway of thermal decomposition differ significantly.

This study presents the synthesis and spectral analysis of new derivatives of 1,2,4-triazole-3-thione and 1,3,4-thiadiazole. New compounds were prepared by cyclization reaction of acyl thiosemicarbazide derivatives in the presence of alkaline and acidic media. All synthesized compounds were screened for their in vitro antibacterial activity by using the agar dilution technique. Six of the compounds had potential activity against Gram-positive bacteria (minimal inhibitory concentration [MIC] = 15.63–500 μg/mL). Some compounds showed good activity especially against Bacillus subtilis ATCC 6633 (MIC = 15.63–250 μg/mL), Staphylococcus aureus ATCC 25923 (MIC = 31.25–250 μg/mL), and Micrococcus luteus ATCC 10240 (MIC = 125–250 μg/mL). Graphical abstract

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.

Two new 1,2,4-triazole-containing alkenoic acid derivatives were obtained from the reaction of N -phenyl-(pyridin-2-yl)carbohydrazonamide with itaconic anhydride, depending on the reaction conditions. The structures of 2-((4-phenyl-5-(pyridin-2-yl)-4 H -1,2,4-triazol-3-yl)methyl)acrylic acid or ( E )-2-methyl-3(4-phenyl-5-(pyridine-2-yl)-4 H -1,2,4-triazol-3-yl)acrylic acid were confirmed by means of 1D and 2D NMR spectroscopic data as well as by single-crystal X-ray diffraction analysis. The experiential 1 H and 13 C chemical shifts were compared with those calculated with B3LYP, EDF1, and EDF2 density functional theories. The theoretical study of the observed terminal-to-internal alkene isomerization was performed with density functional (DFT) B3LYP/6-31+G ∗ method using SM8 water and DMF solvation models. Antimicrobial activities of the newly prepared alkenoic acid derivatives were verified experimentally by a broth microdilution method.

Sodium salt of pyridine-3,5-dicarboxylic acid (H2pdc) reacts with the chloride (or nitrate) salt of lanthanides(III) (from La to Lu, except Pm) under hydrothermal conditions to form different kinds of coordination frameworks. The compounds of the general formula Ln2pdc3·nH2O (pdc2− = C5H3N(COO)22−, n = 2.64–14) are characterized in the solid state by elemental analysis, IR spectroscopy, TG-DSC and TG-FTIR analyses, single-crystal X-ray diffraction, and X-ray powder diffraction (XRPD) techniques as well as fluorescent spectroscopy. The crystalline compounds form isostructural groups: Sm-Gd, Tb-Er and Tm-Lu. The crystal structures of [Ho2pdc3(H2O)2]·0.64H2O (1), [Er2pdc3(H2O)2]·0.68H2O (2) and [Yb4pdc6(H2O)18]·10H2O (3) compounds are reported. The compounds 1 and 2 are built up from metallic centrosymmetric dimers connected by pdc2− ligands into the 3D frameworks. There are observed 1D channels occupied by water molecules. In compound 3, the four Yb(III) centers are bridged through pdc2− ligands into the cyclic tetranuclear structure. These molecules are further assembled into a 3D supramolecular framework. This appears to be a rare example of cyclic polynuclear compounds generated by lanthanide(III) ions and polycarboxylate ligands. The luminescent properties of the complexes in visible and infrared regions upon UV excitation are discussed.

The 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.

Hydrothermal reaction of lanthanide(III) (Nd, Er and Tm) chloride with sodium salt of 4,4′-oxybis(benzoic) acid (H2oba) leads to the formation of two types of monocrystals: prismatic [Nd(Er)(Hoba)(oba)(H2O)2]·0.8H2O (1, 2) and plate-shaped [Tm2oba3(H2O)4]·1.38H2O (3) for which single-crystal X-ray measurements were performed. Isomorphous compounds 1 and 2 consist of eight-coordinated lanthanide ions bonded with oba, Hoba and aqua ligands into the 2D layers. In the structure 3 two types of Tm(III) centers are bridged by oba linkers into 2D layer architecture. Uncoordinated water molecules are located within the cavities between layers. Furthermore, the ATR-IR spectra of isolated monocrystals and thermal behaviours of the compounds are discussed.

Preparation, crystal structures and magnetic properties of new heterodinuclear Cu II Gd III ( 1 ) and Cu II Tb III ( 2 ) complexes [CuLn(L)(NO 3 ) 2 (H 2 O) 3 MeOH]NO 3 ·MeOH (where Ln = Gd, Tb) with the hexadentate Schiff-base compartmental ligand N , N ′-bis(5-bromo-3-methoxysalicylidene)propylene-1,3-diamine (H 2 L = C 19 H 20 N 2 O 4 Br 2 ) ( 0 ) have been described. Crystal structure analysis of 1 and 2 revealed that they are isostructural and form discrete dinuclear units with dihedral angle between the O1Cu1O2 and O1Gd1/Tb1O2 planes equal to 2.5(1)° and 2.6(1)°, respectively. The variable-temperature and variable-field magnetic measurements indicate that the metal centers in 1 and 2 are ferromagnetically coupled ( J = 7.89 cm −1 for 1 ). Crystal and molecular structure of the Schiff base ligand ( 0 ) has been also reported. The complex formation changes the conformation of Schiff base ligand molecule.

A new 1,2,4-triazole derivative, 2-(4-phenyl-5-pyridin-2-yl-4H-1,2,4-triazol-3-yl)cyclohexanecarboxylic acid, C20H20N4O2 (I), and its dimethyl sulfoxide solvate 1:1 (II) have been synthesized and their crystal structure was established. Compound (I) was screened for its antiproliferative and antiinflammatory activity. Structural analysis indicated the substantial difference between two symmetry independent molecules in (I) and this in (II), it manifests in the relative orientation of pyridine/phenyl and triazole rings, as well as in the orientation of carboxyl group with respect to cyclohexane ring. The molecules A and B in the crystal (I) form two hydrogen-bonded chains through O–Hcarboxyl and Ntriazole atoms, giving separate catemers of symmetry independent molecules. The catemer of (IA) running along the 21 axis is homochiral, while the catemer (IB) is racemic—formed about the c glide plane. In the crystalline solvate (II) complexation of (I) with DMSO induced enantiomeric self-resolution. Obtained crystals are racemic twins, in which each part is built of one enantiomer of (I) having the relative configuration 11S,12R or 11R,12S. A pair of host–guest molecules is linked by the O–Hcarboxyl⋯ODMSO hydrogen bond.

The crystal structure and FTIR spectrum of 3-formylchromone (0) have been analysed. A new organic ligands, 3-(anilinomethylene)-2-methoxychroman-4-one (1) and 3-(1′,4′-benzodioxan-6′-aminomethylene)-2-methoxychroman-4-one (2) were synthesized. The products of reactions between 3-formylchromone and aniline and 6-amino-1,4,-benzodioxane were studied by elemental analysis, FTIR spectroscopy, thermal analysis and X-ray crystallography. It has been found that these reactions allow to obtain derivatives of 4-chromanones from 3-formylchromone by the mechanism of nucleophilic addition, accompanied by the opening of the pyrone ring. The experimental results indicate that compounds (1) and (2) are thermal stable up to 90 and 100 °C, respectively. The FTIR spectra and X-ray analysis showed the present of methoxy-group in these compounds.

Reaction of 4-phenyl-4H-1,2,4-triazole-3-thione with ethyl bromoacetate has led to the formation of ethyl [(4-phenyl-4H-1,2,4-triazol-3-yl)sulfanyl]acetate 1, the structure of which was confirmed by X-ray analysis. In the next reaction with 80% hydrazide hydrate, appropriate hydrazide 2 was obtained, which in reaction with isothiocyanates was converted to new acyl derivatives of thiosemicarbazides 2, 3, 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h. The cyclization of these compounds in alkaline media has led to formation of new derivatives of 5-{[(4-phenyl-4H-1,2,4-triazole-3-yl)sulfanyl]methyl}-4H-1,2,4-triazole-3(2H)-thiones 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4j. The structure of the compounds was confirmed by elementary analysis and IR, 1H-NMR, 13C-NMR, and MS spectra. Compounds 2, 3, 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h and 4a, 4b, 4c, 4d, 4e, 4f, 4g were screened for their antimicrobial activities, and the influence of the compounds 4a, 4b, and 4e, 4f, 4g on the central nervous system of mice in behavioral tests was examined. J. Heterocyclic Chem., (2011).

An analysis of the products of the reaction of N 3 -phenylbenzamidrazone with cis -1,2-cyclohexanedicarboxylic anhydride at various temperatures is presented. The identification of the reaction products is carried on with the support of computational techniques. The most stable conformers of the isoindole and triazole derivatives are found within the DFT approach. The theoretical calculations reveal the possible structure of a triazole derivative not available experimentally because of the presence of two diastereoisomers of equal energy.

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.

By the reaction aminomethylation, chloromethylation and acylation of 4-methyl-4H-1,2,4-triazole-3-thiol, 4-methyl-1-substituted-1H-1,2,4-triazole-5(4H)-thione 1-8 were obtained. Molecular structure of the obtained compounds was confirmed by an elemental analysis, IR, 1H NMR and 13C NMR spectra and additionally by X-ray analysis for 2. Six new compounds 1,2,4-7 were tested for antibacterial activity against Mycobacterium smegmatis, Mycobacterium phlei and avirulent strain Mycobacterium H37Ra.

(Z)-3-(3,4-diaryl-1,2,4-triazole-5-yl)prop-2-enoic acid derivatives were obtained in the course of the reaction of N 3-substituted amidrazones with maleic anhydride, and isomerized into the (E) isomers by heating under reflux in acetic acid solution. The molecular structure of the compounds obtained was confirmed by IR and 1H NMR spectroscopy, and by X-ray crystallography for (2E)-3-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)prop-2-enoic acid. The antiviral and immunomodulating activity of several of the compounds was examined.

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) A, b = 15.099(5) A, c = 13.248(4) A, 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.

The mononuclear complex [Na(C7H6O4)(H2O)3](C7H5O4) · 2H2O has been synthesized and characterized by IR, single crystal X-ray and thermal analysis. The compound crystallizes in the monoclinic space group P21 with a = 3.623(2) A, b = 15.872(6) A, c = 15.650(5) A, β = 93.13(4)°, V = 896.6(7) A3 and Z = 2. The central sodium ion is six coordinated with distorted octahedral geometry by two oxygen atoms from two bridging 3,5-dihydroxybenzoate ligands and four ones from different water molecules. The notable feature of the title complex is the formation of a three-dimensional network, through the combination of coordination bonds, hydrogen bonds and π···π interactions. There are one-dimensional channels in the structure, filled in by water molecules. The compound dehydrates in the temperature range of 70–125 °C and then is stable up to 230 °C. The mononuclear complex [Na(C7H6O4)(H2O)3](C7H5O4) · 2H2O has been synthesized and characterized by IR, single crystal X-ray and thermal analysis.

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.

Crystalline solvates of olanzapine (1), 2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno[2,3-b][1,5]benzodiazepine, have been characterized by an X-ray analysis and thermal (DSC) data. Crystallization of 1 from ethanol gives a solid containing both water and ethanol molecules; the solvate 1 · H2O · EtOH (2:2:1) is monoclinic with the space group P21/c and the unit-cell volume V = 3752.8(12) A3. Butan-2-ol forms with 1 solvate which is also a three-component phase, 1 · H2O · BuOH, but its stoichiometry is different (1:1:1). The space group for this crystal is P21/c and the unit-cell volume V = 2216.5(7) A3. Crystalline olanzapine dichloromethane solvate (2:1), 1 · CH2Cl2, is triclinic with the space group P 1 ¯ . The characteristic feature of all crystal structures is presence of a pair of olanzapine molecules which form dimer stabilized by multiple weak C–H⋯π interactions between the N-methylpiperazine fragment and the phenyl / thiophene systems. Theoretical calculations have been performed indicating that the total C–H⋯π binding energy is about 8 kcal mol−1. In the crystal structure, the self-assembled olanzapine molecular dimers are arranged into parallel crystal planes. Packing of the layers proceeds in two ways in which structural motives are replicated by (i) perpendicular translation forming columns, and (ii) rotation around the twofold screw axis (parallel to the layer).