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Proanthocyanidin rich plant extracts derived from grape seed extract (GSE), hawthorn and cranberry are on markets for their preventive effects against cardiovascular diseases and uroinfections in woman. However, the importance [...]

Research has been conducted on the DNA-peptide cross-linking. The study of this cross-linking carried out via peptide attachment to the ruthenium intercalator demonstrate that these peptides provide functional groups which react with the oxidized DNA producing cross-links.

Slow inactivation of voltage-gated Na channels is kinetically and structurally distinct from fast inactivation. Whereas structures that participate in fast inactivation are well described and include the cytoplasmic III-IV linker, the nature and location of the slow inactivation gating mechanism remains poorly understood. Several lines of evidence suggest that the pore regions (P-regions) are important contributors to slow inactivation gating. This has led to the proposal that a collapse of the pore impedes Na current during slow inactivation. We sought to determine whether such a slow inactivation-coupled conformational change could be detected in the outer pore. To accomplish this, we used a rapid perfusion technique to measure reaction rates between cysteine-substituted side chains lining the aqueous pore and the charged sulfhydryl-modifying reagent MTS-ET. A pattern of incrementally slower reaction rates was observed at substituted sites at increasing depth in the pore. We found no state-dependent change in modification rates of P-region residues located in all four domains, and thus no change in aqueous accessibility, between slow- and nonslow-inactivated states. In domains I and IV, it was possible to measure modification rates at residues adjacent to the narrow DEKA selectivity filter (Y401C and G1530C), and yet no change was observed in accessibility in either slow- or nonslow-inactivated states. We interpret these results as evidence that the outer mouth of the Na pore remains open while the channel is slow inactivated. KEY WORDS: gating * cysteine-scanning mutagenesis * methanthiosulfonate * NaV1.4

Research has been conducted on the unsymmetrically substituted singly bridged macrocyclic phosphazene compounds. The added chiral shift reagent, chiral solvating agent and (super)31 P NMR spectroscopy have been used to demonstrate that these compounds are the racemic mixture diastereoisomers on symmetrically substituted diastereoisomeric analogues.

Research has been conducted on the organosulfur compounds. The use of reagents in preparing thioamides, thioketones and thiolactams and the utility of P (sub)4 S (sub)10/hexamethyldisiloxane as a thionating agent are discussed.

Research has been conducted on the organometallic compounds. The organolithium reagent addition to corannulene has been investigated and the route to 1-alkyl-1,2-dihydrocorannulenes has been developed and is described.

Research has been conducted on fluorinated and nonfluorinated alcohols. The interactions of these alcohols with trans-stilbene have been investigated in the presence of electrophilic reagents and the results indicate that these interactions produce alpha-keto ethers which are dependent on the alcohols' fluorination degree and the reaction time.

Research has been conducted on the allyl aromatic compounds. The synthesis of these compounds which does not involve metal-containing reagents or catalysts has been investigated and the results are reported.

Research has been conducted on Cr (super)III (X (sub)4 SQ) (sub)3 where SQ= o-semiquinonate and X= Cl abd Br. The treatment of this compound with acetonitrile has been carried out and the results indicate that the compound undergoes a rapid ligand exchange reaction with the solvent molecules or the nitrogen-donor chelate reagents in polar solvents.

Research has been conducted on hydroxulamine-based electrophilic ammonia equivalents in the 2-oxazolidinone N-amination. The comparison of these equivalents has revealed that the combination of sodium hydride and O-(p-nitrobenzoyl)hydroxylamine in dioxane is a superior reagent for the amination reaction.

Research has been conducted on the psi[(E)-CH=CMe]- and psi[(Z)-CH=CMe]-type alkene dipeptide isosteres. The results of the diastereoselective synthesis of these isosteres which correspond to the dipeptides with N-methylamino acid are reported.

Research has been conducted on the proline dipeptides (Xaa-Pro). The use of the organocopper reagents in the regio- and stereoselective synthesis of (E)-alkene Ser-Pro dipeptide isoesters with trans-Xaa-Pro geometry is described.

Research has been conducted on the biomolecules' photooxidative damage. The effect of the UVA-irradiation on the photo-Fenton reagents has been investigated and the results indicate that this irradiation releases radicals inducing strand breaks.

Research has been conducted on the acyclic and cyclic acetals of carbonyl compounds. The formation of these acetals carried out under the mild reaction conditions in the presence of the catalytic amount of tetrabutylammonium tribromide and trialkyl orthoformate and the details are reported.

Research has been conducted on the alpha-phosphono lactams. The conversion of N-alkyl lactams into alpha-phosphono lactams carried out via the procedures involving lactam enolate formation and reaction with phosphorus electrophile is described.

Research has been conducted on the free unsaturated beta-hydroxy acids. The utility of the lithio thimethylsilyl butenoates used as reagents for the synthesis of these beta-hydroxy acids has been tested and the details are reported.

Research has been conducted on tributylphosphine. Results indicate that this compound is a promoting agent for nucleophile and aziridine ring opening carried out in producing bifunctional products.

Research has been conducted on the acetal and 1,3-oxazolidine rings. The reactions of these ring have been examined via the use of iodosilane equivalent reagents and the details are presented.

Research has been conducted on the alpha-galactosyl ceramide. The synthesis of this stimulatory agent for the immunological process which is mediated by CD1 molecules is described.

Research has been conducted on the alpha-amidoalkylphenyl sulfones. The results of the reaction of these sulfones with functionalized allylzinc reagents indicate that the sulfones behave as N-acylimino equivalents.

Research has been conducted on the electrophile equivalents Cl (super)+, Br (super)+, SCN (super)+ and NO (sub)2 (super)+. The generation of these electrophiles and their application in electrophilic aromatic substitution reaction of different substrates are discussed.

Research has been conducted on the allyl metal reagents. The additions of these reagents to benzaldehydes have been investigated and the results are reported.

Research has been conducted on the alkenyl-beta-dicarbonyl compounds. The results of the cyclofunctionalization of these differently substituted compounds carried out via the use of electrophilic reagents, including iodine and phenylselenenyl bromine, are reported.

Research has been conducted on Gloeophyllum trabeum, a brown-rot basidiomycete which uses quinone redox cycle to produce a biodegradative system component Fenton reagent. The characterization of the quinone reductase, mRNA and gene encoding this enzyme from G. trabeum has been carried out and the results are reported.

The authors review the publications on Lewis acid-catalyzed reactions. The topics of interest include C-C bond formation, oxidation and reduction and cyclization reactions.

Research has been conducted on the methyl 2-((succinimidooxy)carbonyl)benzoate. The description of this reagent for N-phthaloylation of amino acids and amino acid derivatives is presented.

Research has been conducted on the fragrant target molecules, cis-3-methyl-4-decanolide and aerangis lactone. The route to these molecules which does not require air-sensitive reagents has been developed and the details are presented.

Research has been conducted on the polycyclic ethers. The synthesis of the medium size cyclic ethers has been carried via the ketene acetal triflate palladium-catalyzed coupling with the organozinc reagents and the details are presented.

Research has been conducted on the enantiomerically enriched ferrocene derivatives. The results of the enantioselective addition of the aryllithium to 6-(dimethylamino)fulvene carried out in toluene in the presence of (-)-sparteine are discussed.

Research has been conducted on the use of the rhodium catalysts and organoboron reagents in the reactions. The mechanism establishing the catalytic cycle of the rhodium-catalyzed 1,4-addition of organoboronin acid has been developed and is described.

Research has been conducted on the silicon, silica and silicate form. The use of the silicon dioxide sources as reagents in the reaction with dimethyl carbonate in producing tetramethoxysilane ia discussed.

The authors review the publications on the radical and single-electron-transfer chemistry. The topics of interest include the mechanism of the alkane activation reaction, radical chemistry, traditional reagents and electrophilic radical-like species.

Research has been conducted on the 3,4-cyanomethyl substituted thiophenes. The reaction of these compounds with thionyl chloride has been carried out in the presence of base in producing dicyano substituted thieno(3,4-c)thiophenes and the details are reported.