Combination of Phenylsilsesquioxane and Acetate Ligands as an Approach to a Record High Nuclear CuNa-Cage. Synthesis, Unique Structure, and Catalytic Activity.

Self-assembly synthesis of mixed-ligand (silsesquioxane/acetate) complex allows to isolate record high nuclear copper(II) Cu-cage (1). In the presence of two additional sodium ions, a unique molecular architecture, with triple combination of ligands (cyclic and acyclic silsesquioxanes as well as acetates), has been formed. The structure was established by single-crystal X-ray diffraction based on the use of synchrotron radiation.

An octanuclear 3-phenyl-5-(2-pyridyl)pyrazolate/phenylsilsesquioxane complex: synthesis, unique structure, and catalytic activity.

The first metallasilsesquioxane bearing pyrazolylpyridine ligands, the Cu-based complex 1, adopts a cage-like structure with two zigzag-type copper tetramers sandwiched by two cyclic Si silsesquioxane ligands. The four 3-phenyl-5-(2-pyridyl)pyrazolate ligands in 1 exhibit dual (chelating and bridging) modes of ligation. Compound 1 is very active in the oxidation of alkanes and alcohols.

Cu-Methylsilsesquioxane Cage Decorated with Cu(dppe) Moieties for Mild Oxidative Functionalization of Alkanes.

We report a high nuclear (Cu) complex synthesized via the self-assembly of copper-methylsilsesquioxane induced by the complexation with 1,2-bis(diphenylphosphino)ethane (dppe). The structure includes two cationic Cu(dppe) moieties and an anionic silsesquioxane cage of an unprecedented Cu structural type. The Cu cage fragment exhibits a unique () combination of Si-cyclic/Si-acyclic silsesquioxane ligands and () encapsulation of two different chloride and carbonate species.

An ionic CuNa-phenylsilsesquioxane/bis(triphenylphosphine)iminium complex: synthesis, unique structure, and catalytic activity.

The synthesis of a high nuclear (CuNa) complex 1 the self-assembly of copper(II) phenylsilsesquioxane induced by complexation with bis(triphenylphosphine)iminium chloride (PPNCl) was successfully achieved. This complex, which includes two bis(triphenylphosphine)iminium PPN cations, represents the first example of a metallasilsesquioxane/phosphazene compound. The CuNa-silsesquioxane cage demonstrates a nontrivial combination of two pairs of Si-cyclic/Si-acyclic silsesquioxane ligands and a fusion of two SiCuNa fragments, combined the central ninth copper ion.

Rational (supra)molecular design and catalytic activity of cage-like Cu-based phenylsilsesquioxanes.

An extended (, 19 distinct species) family of cage-like Cu-phenylsilsesquioxanes allowed us to accentuate the general regularities behind their structural organization. Influencing factors, namely the (i) size of external alkali metal ions (from Li to Cs) and (ii) nature of bridging linkers (including the smallest possible ones, like a water molecule) on the self-assembly/supramolecular assembly of such Cu-building blocks have been thoroughly explored. A CuK-based complex has been evaluated as a precatalyst in the oxidation of alkanes (cyclohexane, -heptane, methylcyclohexane) and alcohols.

Fe(III)-Based Phenylsilsesquioxane/Acetylacetonate Complexes: Synthesis, Cage-like Structure, and High Catalytic Activity.

Unprecedented iron-based silsesquioxane/acetylacetonate complexes were synthesized. The intriguing cage-like structure of compounds is alkaline metal-dependent: the FeLi complex includes condensed Si-silsesquioxane and four acetylacetonate ligands; the FeNa complex exhibits two cyclic Si-silsesquioxane and eight acetylacetonate ligands, while the FeK complex features two cyclic Si-silsesquioxane and six acetylacetonate ligands. The latter case is the very first observation of small trimeric silsesquioxane ligands in the composition of cage-like metallasilsesquioxanes.

Colliding heavy nuclei take multiple identities on the path to fusion.

The properties of superheavy elements probe extremes of physics and chemistry. They are synthesised at accelerator laboratories using nuclear fusion, where two atomic nuclei collide, stick together (capture), then with low probability evolve to a compact superheavy nucleus. The fundamental microscopic mechanisms controlling fusion are not fully understood, limiting predictive capability.

Novel Highly Efficient Antibacterial Chitosan-Based Films.

In this study, we elaborated new chitosan-based films reinforced by iron(III)-containing chitosan nanoparticles Fe(III)-CS-NPs at different concentrations. We found that the optimum concentration of Fe(III)-CS-NPs for the improvement of antibacterial and mechanical properties of the films was 10% (σ = ca. 8.

Chitosan-Based Ciprofloxacin Extended Release Systems: Combined Synthetic and Pharmacological (In Vitro and In Vivo) Studies.

Ciprofloxacin is one of the most effective antibiotics, but it is characterized by a range of side effects. Elaboration of drug-releasing systems which allow to diminish toxicity of ciprofloxacin is a challenging task in medicinal chemistry. The current study is focused on development of new ciprofloxacin releasing systems (CRS).

The first selenium containing chitin and chitosan derivatives: Combined synthetic, catalytic and biological studies.

Ultrasonic approach to the synthesis of the first selenium-containing derivatives of chitin and chitosan has been developed. The synthetic procedure is simple, provides high yields, does not require harsh conditions, and uses water as the reaction medium. The elaborated chitin and chitosan derivatives and their based nanoparticles are non-toxic and possess high antibacterial and antifungal activity.

Mass Equilibration and Fluctuations in the Angular Momentum Dependent Dynamics of Heavy Element Synthesis Reactions.

Mass and angle distributions for the ^{52}Cr+^{198}Pt and ^{54}Cr+^{196}Pt reactions (both forming ^{250}No) were measured and subtracted, giving new information on fast quasifission mass evolution, and the first direct determination of the dependence of sticking times on angular momentum. TDHF calculations showed good agreement with average experimental values, but experimental mass distributions unexpectedly extended to symmetric splits while the peak yield remained close to the initial masses. This implies a strong role of fluctuations in mass division early in the collision, giving insights into the transition from fast energy dissipative deep-inelastic collisions to quasifission.

Chitosan derivatives and their based nanoparticles: ultrasonic approach to the synthesis, antimicrobial and transfection properties.

In the present work, we demonstrate that alkylation of chitosan by alkyl halides, aza-Michael reaction with chitosan, and Ad-E reaction of chitosan with aldehydes can be efficiently mediated by ultrasound. An optimization of ultrasonic irradiation parameters allowed us to (i) accelerate the rate of the reactions dramatically, (ii) achieve high selectivity, and (iii) preserve integrity of the polysaccharide backbone avoiding its depolymerization. We evaluated antibacterial/antifungal and transfection activity of 8 different derivatives of chitosan and their based nanoparticles in vitro.

Design of new anti-Alzheimer drugs: ring-expansion synthesis and synchrotron X-ray diffraction study of dimethyl 4-ethyl-11-fluoro-1,4,5,6,7,8-hexa-hydro-azonino[5,6-]indole-2,3-di-carboxyl-ate.

The title compound, CHFNO, is the product of a ring-expansion reaction from a seven-membered fluorinated hexa-hydro-azepine to a nine-membered azonine. The nine-membered azonine ring of the mol-ecule adopts a conformation. The C=C and C-N bond lengths [1.

A New Bacillus licheniformis Mutant Strain Producing Serine Protease Efficient for Hvdrolvqis of Sov Meal Proteins.

Induced mutagenesis with y-irradiation of the industrial strain Bacillus licheniformis-60 VKM B-2366,D was used to obtain a new highly active producer of an extracellular serine protease, Bacillus licheni- formis7 145. Samples of dry.concentrated preparations of serine protease produced by the original and mutant strains were obtained, and identity of their protein composition was'established.

Ring-expansion synthesis and crystal structure of dimethyl 4-ethyl-1,4,5,6,7,8-hexa-hydro-azonino[5,6-]indole-2,3-di-carboxyl-ate.

The title compound, CHNO, is the product of a ring-expansion reaction from a seven-membered hexa-hydro-azepine to a nine-membered azonine. The azonine ring of the mol-ecule adopts a chair-boat conformation. In the crystal, mol-ecules are linked by bifurcated N-H⋯(O,O) hydrogen bonds, generating [010] zigzag chains.

Crystal structures of -[(4-phenyl-thia-zol-2-yl)carbamo-thio-yl]benzamide and -{[4-(4-bromo-phen-yl)thia-zol-2-yl]carbamo-thio-yl}benzamide from synchrotron X-ray diffraction.

The title compounds, CHNOS, (I), and CHBrNOS, (II), are potential active pharmaceutical ingredients. Compound (I) comprises two almost planar fragments. The first is the central (carbamo-thio-yl)amide (r.

[Investigation of structural characteristics of initial substances of ibuprofen and micronization impact].

Structural characteristics of ibuprofen substances manufactured by different firms and the impact of micronization on them were compared. The study showed that the use of X-ray diffraction methods was necessary for certification of medicinals (crystalline) since only such methods provided information on the substance crystal structure, the molecular state and polymorphous forms.

Predominant time scales in fission processes in reactions of S, Ti and Ni with W: zeptosecond versus attosecond.

The inhibition of fusion by quasifission is crucial in limiting the formation of superheavy elements in collisions of heavy nuclei. Time scales of ∼10(-18)  s inferred for fissionlike events from recent crystal blocking measurements were interpreted to show either that quasifission itself is slower than previously believed, or that the fraction of slow fusion-fission is higher than expected. New measurements of mass-angle distributions for (48)Ti and (64)Ni bombarding W targets show that in these reactions quasifission is the dominant process, typically occurring before the system formed after contact has made a single rotation, corresponding to time scales of ≤10(-20)  s.

Cytotoxic activity of a new paclitaxel formulation, Pacliex, in vitro and in vivo.

Background: The paclitaxel formulation, Taxol (Bristol-Myers Squibb), is one of the most effective anticancer agents used today. However; it is associated with serious side effects believed to be caused by the Cremophor EL used for its formulation.

Aim: To evaluate the cytotoxic activity of a new paclitaxel formulation, Pacliex (developed by Oasmia Pharmaceutical, Uppsala, Sweden), a mixed micelles preparation in which an amphiphilic synthetic derivative of retinoic acid replaced Cremophor EL/ethanol vehicle.

pH modulation of large conductance potassium channel from adrenal chromaffin granules.

We report here that large conductance K(+) selective channel in adrenal chromaffin granules is controlled by pH. We measured electrogenic influx of (86)Rb(+) into chromaffin granules prepared from bovine adrenal gland medulla. The (86)Rb(+) influx was inhibited by acidic pH.

Primary structure of ferredoxin from bovine kidney mitochondria.

Kidney mitochondrial ferredoxin (renodoxin) is a component of the cytochrome P-450-dependent enzymatic system whose main function is the hydroxylation of vitamin D3 in the 1alpha- and 24-positions. The complete amino acid sequence of renodoxin was determined by protein chemistry and mass spectrometry. The mature renodoxin has 128 amino acid residues.

ATP-sensitive K+ transport in adrenal chromaffin granules.

In the present study the influx of 86Rb+, a K+ analogue, was studied in mitochondria, microsomes and chromaffin granules prepared from adrenal gland medulla. The most active electrogenic 86Rb+ transport was found in the membrane fraction identified as chromaffin granules by marker enzyme estimation. The transport was found to be sensitive to ATP, ATP gamma S, ADP and to the triazine dyes, but not to AMP and cAMP.

Modification of the mitochondrial sulfonylurea receptor by thiol reagents.

The purpose of this study was to investigate the effects exerted by thiol-modifying reagents on themitochondrial sulfonylurea receptor. The thiol-oxidizing agents (timerosal and 5, 5'-dithio-bis(2-nitrobenzoic acid)) were found to produce a large inhibition (70% to 80%) of specific binding of [(3)H]glibenclamide to the beef heart mitochondrial membrane. Similar effects were observed with membrane permeable (N-ethylmaleimide) and non-permeable (mersalyl) thiol modifying agents.

Effects of K+ channel inhibitors on potassium transport in bovine adrenal chromaffin granules.

The Ca(2+)-independent K+ selective channel in the membrane of adrenal gland chromaffin granules has earlier been identified. In the present report we describe new properties of this potassium channel using 86Rb+, a K+ analogue, flux measurements. The studies are performed in membrane vesicles prepared from chromaffin granules.