Pseudo-polymorphism of a camphor α-cyclodextrin complex.

Crystalline products of vapor diffusion of an alcoholic solution of 1R,4R-camphor into an aqueous solution of α-cyclodextrin were prepared and subjected to X-ray structure analysis. Two different forms were obtained: a dimeric cavity formed by head-to-head association of cyclodextrin (phase A), and a complex set of monomeric cavities (phase B). Both contain camphor molecules orientationally disordered inside cavities.

Platinum(II) complex with 4-nitro-N-(pyridin-2-ylmethylidene)aniline: synthesis, characterization, crystal structure and antioxidant activity.

A novel complex has been prepared using the (E)-4-nitro-N-(pyridin-2-ylmethylidene)aniline bidentate Schiff base ligand and PtCl, namely, dichlorido[(E)-4-nitro-N-(pyridin-2-ylmethylidene)aniline-κN,N']platinum(II) acetonitrile hemisolvate, [PtCl(CHNO)]·0.5CHCN, 1. According to the X-ray measurements of the crystal structure, the Pt ion adopts a PtClN square-planar coordination.

Potent cyclometallated Pd(II) antitumor complexes bearing α-amino acids: synthesis, structural characterization, DNA/BSA binding, cytotoxicity and molecular dynamics simulation.

A rational approach was adopted to design high-potential metal-based antitumor agents. A series of organometallic Pd(ii) complexes with a general formula of [Pd{κ2(C,C)-[(C6H4-2)PPh2]CH(CO)C6H4Ph-4}{κ2(N,O)}] (N,O = alanine (Pd-A), valine (Pd-V), leucine (Pd-L), l-isoleucine (Pd-I) and phenylalanine (Pd-F)) were prepared by cyclopalladation of the phosphorus ylide, bridge cleavage reaction and subsequent chelation of natural α-amino acids. The complexes were fully identified using IR and multinuclear 1H, 13C, 31P NMR spectroscopic methods.

Partial in Situ Reduction of Copper(II) Resulting in One-Pot Formation of 2D Neutral and 3D Cationic Copper(I) Iodide-Pyrazine Coordination Polymers: Structure and Emissive Properties.

On the way to copper(I) iodide coordination polymers with specific luminescent properties, the in situ reduction of Cu(II) in the presence of KI and bidentate N-heteroatomic ligand, either pyrazine (pyz) or 4,4'-bipyridine (bpy), resulted in one two-dimensional and two three-dimensional new coordination networks. Starting from Cu(NO)·3HO in the presence of pyz, successive precipitation of known yellow [(CuI)(pyz)], new orange [CuI(pyz)], and new dark blue {[Cu(pyz)]·I} polymeric solids was observed. Starting from the same salt in the presence of bpy resulted in the successive precipitation of known yellow [(CuI)(bpy)] and new brown {[Cu(NO)(bpy)]·I·(dmf·HO)} coordination polymers.

Synthesis, spectral characterization, crystal structure and in vitro DNA/protein binding studies of phosphorous ylide palladacyclic complexes containing azide group.

The reaction between (4-nitrobenzoylmethylene)triphenylphosphorane Pd(II) complex [Pd{κ(2)(C,C)-C₆ H₄PPh₂C(H)CO(C₆ H₄NO₂-4)}(μ-Cl)]₂ and excess of NaN₃ resulted in the μ-N₃ bridged Pd(II) complex [Pd{κ(2)(C,C)-C₆H₄PPh₂C(H)CO(C₆ H₄NO₂-4)}(μ-N₃)]₂ (1), which underwent bridge cleavage reactions with monodentate ligands to afford the monomeric, neutral complexes [Pd{κ(2)(C,C)-C₆ H₄PPh₂C(H)CO(C₆ H₄NO₂-4)}N₃(L)] (L=Me₃Py (1a), PPh₃ (1b)). The complexes were identified and characterized by elemental analyses, infrared (IR), ((1))H, ((13))C{((1))H} and ((31))P{((1))H} NMR spectroscopy. The molecular structure of 1b was determined by single-crystal X-ray diffraction.

In vitro cytotoxicity studies of palladacyclic complexes containing the symmetric diphosphine bridging ligand. Studies of their interactions with DNA and BSA.

The reactions between [Pd2{(C,N)-C6H4CH2NH(Et)}2(μ-X)2] (X = Cl or Br) and 1,2-bis(diphenylphosphino)ethane (dppe) in the 1:1 molar ratio resulted in the dppe-bridged Pd(II) complexes, [Pd2{(C,N)-C6H4CH2NH(Et)}2(μ-dppe)(Cl)2] (1) and [Pd2{(C,N)-C6H4CH2NH(Et)}2(μ-dppe)(Br)2] (2), respectively, which were characterized by elemental analyses, infrared (IR), (1)H- and (31)P{(1)H} NMR spectroscopy. The molecular structure of 1 was determined by single-crystal X-ray diffraction. In vitro cytotoxicity of 1, 2, dppe, PhCH2NH(Et) and cisplatin were carried out against four human tumor cell lines.

Synthesis, biological evaluation, X-ray molecular structure and molecular docking studies of RGD mimetics containing 6-amino-2,3-dihydroisoindolin-1-one fragment as ligands of integrin αIIbβ₃.

A series of novel RGD mimetics containing phthalimidine fragment was designed and synthesized. Their antiaggregative activity determined by Born's method was shown to be due to inhibition of fibrinogen binding to αIIbβ₃. Molecular docking of RGD mimetics to αIIbβ₃ receptor showed the key interactions in this complex, and also some correlations have been observed between values of biological activity and docking scores.

Interactions with β-cyclodextrin as a way for encapsulation and separation of camphene and fenchene.

The separation of isomeric monoterpenes, camphene and fenchene by complexation with β-cyclodextrin is presented. Both of the monoterpenes form complexes with β-cyclodextrin (as shown by both gas chromatography and (1)H NMR) with similar stability constants nevertheless it is possible to separate them by re-crystallization. The crystal structure of β-cyclodextrin with fenchene was also studied by X-ray diffraction.

Structural diversity in native cyclodextrins/folic acid complexes--from [2]-rotaxane to exclusion compound.

The formation of different complexes of folic acid depending on the size of the host cyclodextrin resulting in either an exclusion compound (with the smallest α-cyclodextrin) or 2-rotaxane, where cyclodextrin is threaded over folic acid (with β- and γ-cyclodextrins), is presented. The formation is carried out in water which allows both possible application in pharmaceutical sciences and usage of environmentally friendly "green chemistry". The obtained compounds are thoroughly characterized using one and two dimensional NMR, mass spectrometry, differential scanning calorimetry and thermogravimetric analysis.

Towards a new family of photoluminescent organozinc 8-hydroxyquinolinates with a high propensity to form noncovalent porous materials.

We report on investigations of reactions of tBu(2)Zn with 8-hydroxyquinoline (q-H) and the influence of water on the composition and structure of the final product. A new synthetic approach to photoluminescent zinc complexes with quinolinate ligands was developed that allowed the isolation of a series of structurally diverse and novel alkylzinc 8-hydroxyquinolate complexes: the trinuclear alkylzinc aggregate [tBuZn(q)](3) (1(3)), the pentanuclear oxo cluster [(tBu)(3)Zn(5)(μ(4) -O)(q)(5)] (2), and the tetranuclear hydroxo cluster [Zn(q)(2)](2)[tBuZn(OH)](2) (3). All compounds were characterized in solution by (1)H NMR, IR, UV/Vis, and photoluminescence (PL) spectroscopy, and in the solid state by X-ray diffraction, TGA, and PL studies.

Use of quantitative structure-enantioselective retention relationship for the liquid chromatography chiral separation prediction of the series of pyrrolidin-2-one compounds.

In this work, the enantioseparation of 15 structurally similar chiral solutes is studied, and analysis of the retention factors is performed using a genetic algorithm and multiple linear regression analysis technique. The present quantitative structure-enantioselective retention relationship model generated for retention factors' data has confirmed the importance of a number of descriptors altering the retention behavior and enantioselectivity of the studied compounds. Thus, fragment-based descriptor PSA, which encodes polar surface area, has confirmed the crucial role of heteroatoms in the retention behavior exhibited by pyrroliddin-2-ones.

High-pressure gas hydrates of argon: compositions and equations of state.

Volume changes corresponding to transitions between different phases of high-pressure argon gas hydrates were studied with a piston-cylinder apparatus at room temperature. Combination of these data with the data taken from the literature allowed us to obtain self-consistent set of data concerning the equations of state and compositions of the high-pressure hydrates of argon.

One-dimensional coordination polymers from hexanuclear manganese carboxylate clusters featuring a {Mn(II)4Mn(III)2(mu4-O)2} core and spacer linkers.

The bridging of hexanuclear mixed-valent carboxylate coordination clusters of the type [Mn(6)O(2)(O(2)CR)(10)] (R = CMe(3); CHMe(2)) featuring a {Mn(II)(4)Mn(III)(2)(mu(4)-O)(2)} core by geometrically rigid as well as flexible spacer ligands such as pyrazine (pyz), nicotinamide (na), or 1,2-bis(4-pyridyl)ethane (bpe) results exclusively in one-dimensional (1D) coordination polymers. The formation of {[Mn(6)O(2)(O(2)CCMe(3))(10)(Me(3)CCO(2)H)(EtOH)(na)] x EtOH x H(2)O}(n) (1), {[Mn(6)O(2)(O(2)CCHMe(2))(10)(pyz)(3)] x H(2)O}(n) (2), and {[Mn(6)O(2)(O(2)CCHMe(2))(10)(Me(2)CHCO(2)H)(EtOH)(bpe)] x Me(2)CHCO(2)H}(n) (3) illustrates a surprising preference of the interlinked {Mn(6)} units toward 1D coordination chains. In the solid-state, the observed chain propagation axes are either colinear (1 and 3) or perpendicular (2), whereby crystal packing is further influenced by solvent molecules.

Metal complexes of cinchonine as chiral building blocks: a strategy for the construction of nanotubular architectures and helical coordination polymers.

The first chiral bipyridyl-type metalloligands based on aluminum derivatives of cinchonine (CN-H) were synthesized and characterized by single-crystal X-ray diffraction studies. These bischelate complexes, (CN)(2)AlX [X = Cl (1a), Me (1b)] were found to be effective building blocks for the preparation of novel helical nanotubular architectures as well as chiral bimetallic coordination polymers, as demonstrated by the rational synthesis of a helical structure formed by 1a and ZnCl(2). The applied methodology stands as an exemplary strategy for the rational synthesis of chiral metal-organic frameworks through self-organization driven by nonbonding interactions or coordination, which could potentially find applications in enantioselective separations and catalysis.

Oxygenation of alkylzinc complexes with pyrrolylketiminate ligand: access to alkylperoxide versus oxo-encapsulated complexes.

By variation of the zinc bonded alkyl group significantly different post-oxygenation products, the novel zinc alkylperoxide and the tetranuclear zinc oxo-encapsulated cluster, were derived from the controlled oxygenation of the corresponding alkylzinc complexes with a pyrrolylketiminate ligand.

First determination of volume changes and enthalpies of the high-pressure decomposition reaction of the structure H methane hydrate to the cubic structure I methane hydrate and fluid methane.

Pressure-temperature (P-T) conditions of the decomposition reaction of the structure H high-pressure methane hydrate to the cubic structure I methane hydrate and fluid methane were studied with a piston-cylinder apparatus at room temperature. For the first time, volume changes accompanying this reaction were determined. With the use of the Clausius-Clapeyron equation the enthalpies of the decomposition reaction of the structure H high-pressure methane hydrate to the cubic structure I methane hydrate and fluid methane have been calculated.

Diastereoselective lower rim (1S)-camphorsulfonylation as the shortest way to the inherently chiral calix[4]arene.

[structure: see text]. A diastereomeric mixture of chiral 25-(1S)-camphorsulfonyloxy-26-isopropoxycalix[4]arene 2a (de 15%) and 25-isopropoxy-26-((1S)-10-camphorsulfonyl)calix[4]arene 2b has been obtained by asymmetrical lower rim (1S)-camphorsulfonylation of the monoisopropoxycalix[4]arene. Pure diastereomer 2a has been obtained by simple crystallization, and its absolute configuration has been determinated by X-ray analysis.

Templated crystal nucleation: mixed crystals of very different copper(II) N,N',N''-trimethyltriazacyclononane complexes.

Templation of a daughter phase by a parent crystal results from an equilibrating mixture of two very different copper(ii) N,N',N''-trimethyltriazacyclononane complexes.