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A new approach is described that is employed for an efficient NMR-based mapping of the disulfide bridges in cysteine-rich peptides. The application of the method to the three-disulfide-bridged conotoxin, [mu]-conotoxin SxIIIA is shown to be extremely effective and efficient.

The versatile application of the sulfonyl group to azulene systems is discussed. A convenient synthesis method of 2-substituted azulenes based on sulfonyl group directed lithiation is reported.

The visual fluorescent assay is used for the detection of triacetone triperoxide (TATP). Aryl sulfoxides have application in the detection of species beyond oxidants and the titration of a pyrene derivative with metal ions such as [Li.sup.+] and [Zn.sup.2+] has led to the enhancement of fluorescence.

Relative rate methods are used for rate constants for the gas-phase reactions of divinyl sulfoxide (DVSO) with N[O.sub.3] radicals and [O.sub.3] and rate constants for the reaction with OH radicals are measured. The results obtained for the DVSO are compared for the corresponding reactions of dimethyl sulfoxide.

Rhodium-catalyzed aryl- and alkylthiolation reaction of fluorobenzene with disulfides is applied on the single bond metathesis of CF and SS bonds. The studies have shown that the rhodium-catalyzed method has a notable mode of CF activation by the transition metal catalyst and has offered a broad scope for the manipulation of organosulfur compounds.

The studies about the human NTPDase 2 activity, which is inactivated by membrane perturbation that disrupts interactions of the transmembrane domains and inhibited by p-chloro-mercuriphenylsulfonate (pCMPS), a sulfhydryl reagent are reported. The loss of the ATPase activity of human NTPDase 2 in the presence of pCMPS possibly results from the disturbance of both transmembrane domain interaction and its active site and is attenuated when the enzyme is cross-linked by glutaraldehyde.

[alpha]'-Arylsulfonyl enones are efficient bidendate dienophiles for the Cu(II)-bis(oxazoline) catalyzed enantioselective Diels-Alder reaction with a number of dienes, which has afforded the corresponding products with good to high enantiomeric excesses. The resulting products are alkylated and the sulfone is removed, so [alpha]'-arylsulfonyl enones are regarded as surrogates of simple monodentate enones, which are poor dienophiles with this catalytic system.

Thioester molecules, S-methyl thioacetate, C[H.sub.3]C(O)SC[H.sub.3], are examined by HeI photoelectron spectroscopy (PES) and valence photoionization studies by using synchrotron radiation in the same energy range. The photodissociation behavior of C[H.sub.3]C(O)SC[H.sub.3] is divided into three well-defined energy regions and vibronic structure is seen in the valence synchrotron photoionization process.

Several analyses are conducted to study the crystal structure of the complex thioflavin T, which is bound to the peripheral site of Torpedo californica acetylcholinesterase. The analysis proves that the thioflavin T is an extremely sensitive fluorescent reporter of ligand binding to the acylation site.

The characterization of the human Urm1 and Saccharomyces cerevisiae Uba4 proteins, which have similar sequence as found in MOCS2A and MOCS3, two proteins essential for the biosynthesis of the molybdenum cofactor (Moco) in humans is reported. The functional similarities observed between Uba4 and MOCS3 demonstrate the evolutionary link between ATP-dependent protein conjugation and ATP-dependent cofactor sulfuration.

The article discusses the liquid phase adsorption exhibited by the microporous coordination polymers (MCPs), which are capable of adsorbing large quantities of the organosulfur compounds. The shape and size of the pore is shown to highly affect the adsorption capacity of a given MCP.

The article discusses a new approach, which uses N-tert-butanesulfinyl aldimines for the asymmetric copper-catalyzed synthesis of [alpha]-amino boronate esters. The method is shown to be extremely effective, as it gives high yields with high diastereoselectivities.

The impact of phenolsulfonphthalein and phenolphthalein on the mechanism of amyloid fibril formation is studied. The three-dimensional assembly of the polyphenol phenolsulfonphthalein is shown to play a very important role in inhibition of the amyloid formation activity.

The complex [[iron(III) (octaphenylsulfonato)porphyrazine].sup.5-] ([Fe.sup.III](Pz)) is synthesized and the p[K.sub.a] values of the axially coordinated water molecules are determined. The results have shown that the [Fe.sup.III](Pz) complex has acted as an effective catalyst in oxidation reactions especially at higher pH.

ZnS powders with primary crystallite sizes of only a few nanometers are prepared by three different synthesis routes. Both of the thioacetamide (TAA)-precipitation routes have led to spherical agglomerates consisting of spherical substructures, whereas the hexamethyldisilathiane agglomerates are assembled from elongated objects.

A series of discrete compounds and supramolecular polymers are prepared by self-assembly of dithioether building blocks and HAu[Cl.sub.4].3[H.sub.2]O. The coordination chemistry of Au(I) complexes with dithioether ligands is examined.

The interaction of a flexible thioether ligand with mercury(II) acetate and iodide has yielded two compounds with structural motifs of a macrocycle and a one-dimensional (1D) polymer, whose structural patterns is dominated by anions and could be reversibly changed. The results have supported the presence of a reversible transition between zero dimensional and 1D structures of mercury complexes using different chemical compounds as the driving force.

The studies about mushroom tyrosinase which behaves as an external monooxygenase and catalyzes the asymmetric oxidation of organic sulfides to corresponding sulfoxides in the presence of suitable reducing agents, catechol are reported. The results provide insight into different experimental mechanism to increase enantioselectivity of tyrosinase activity.

A mild and general procedure is developed for the carbonylation of aryl tosylates and mesylates at atmospheric pressure of carbon monoxide and low temperatures. A commercially available, air stable dccp.2HB[F.sub.4] salt is used as the supporting ligand in this preparation.

The spectroscopic evidence for the formation of an analogous sulfonium ion intermediate in a tetrahydropyran system which negate the [S.sub.N]2 pathway for products formation is described. The results confirm the importance of the Curtin-Hammett principle in which the formation of a low-energy intermediate does not necessitate its involvement in the product-forming pathway.

The first example of highly selective catalytic direct-type addition reactions of sulfonylimidates is presented. Some of the catalyst and reactions discussed are tertiary amines, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) in Mannich-type, Michael-type and azodicarboxylate addition reactions.

The one-step process for conversion of heteroarene-N-oxides to [alpha]-imidazoloheteroarenes by the action of sulfuryl diimidazole at elevated temperatures is described.

Various neutral and anionic cyclodextrin (CD) derivatives are used to study the kinetics of the hydrolysis of 4-methoxybenzenesulfonyl chloride (MBSC) in different surfactant mixed systems. The CD derivatives are found to have no effect on the properties of the surfactant micelles.

Studies suggest that N-methyl-N-4,6-dimethoxy-1,3,5-triazinylmorpholinium salts could be employed as activators of nucleoside methylphosphonates and their thiocongeners.

The electron-diffraction techniques complemented by theoretical methods were used determine the gas phase molecular structure of methyl methanethiosulfonate, C[H.sub.3]S[O.sub.2]SC[H.sub.3]. The formation of both anti and gauche conformer is possible by rotating about S-S bond, but the gauche conformer is found to be more stable.

The use of 2,3-anhydro-D-gulofuranosyl thioglycosides and glycosyl sulfoxides in the synthesis of [alpha]-D-galactofuranosidic bonds that are present in a range of bacterial and fungal glycoconjugates is reported. The glycosyl sulfoxides were found to provide the products in slightly higher yields and selectivity with the best results being obtained with benzylated and benzoylated substrates.

A study rationalized the substituent effects on the rate of radical cyclization of [alpha]-sulfenyl-, [alpha]-sulfinyl-, and [alpha]-sulfonyl-(5R)-5-hexenyl radicals in which R = H, CN, N[O.sub.2], C[H.sub.3] and N[H.sub.2] according to the calculated intrinsic barrier and thermodynamic contributions derived from Marcus theory in conjunction with frontier molecular orbital theory. It is seen that the [alpha]-sulfinyl-5-hexenyl radical exhibits unexpected regioselectivity (93.99:6.01) via the 5-exo mode, whereas the [alpha]-sulfenyl- and [alpha]-sulfonyl-5-hexenyl radicals show increasing branching ratios of the 6-endo product.

Partitionally assembled organosulfur monolayers are prepared by using an electrochemically assisted assembly method on gold films that are preseparated into two regions insulated from each other. The partitionally assembled sulfur-based monolayers with different terminal groups are used to form location-selective nanoparticle assemblies.

The synthesis and application of novel acid catalysts based on sulfonic-modified mesostructured materials is described. It shows better catalytic performance than conventional homogeneous and other heterogeneous catalytic systems.

Two isotopically and structurally labeled Ru-based carbenes were prepared and attached to the surface of monolithic sol-gel glass. The resulting glass-supported complexes exhibited significant catalytic activity in promoting olefin metathesis reactions and provide products of high purity.

The reaction of (eta(super 5)-C2H5)Co(PPh3)2 and an alkynylsulfoxide leading to the direct observation of carbon-sulfur bond activation involving a sulfoxide is described. Transition metal insertion into the carbon-sulfur bond of sulfides to give well-characterized oxidative addition products is also discussed.

Several different computational approaches such as G3MP2B3, G3, B3LYP and CBS-Q were used to compute the gas-phase enthalpies of formation of small sulfur-containing molecules. The different computational schemes are tested in order to know which yields the best results when compared with experimental data.

The reaction of several model organosulfur compounds, such as dimethyl disulfide (CH3SSCH)3, methanethiol (Ch3SH), and dimethyl sulfide (CH3SCH3), with Si(100) at room temperature is studied. It is found that the Auger electron spectroscopy (AES) measurements show that each of these organsulfur compounds has a characteristics saturation coverage and reaction probability for chemisorptions on Si(100).

Impact of organosulfur compounds on reducing heterocyclic aromatic amine and mutagenicity in fried ground beef patties is examined.

The organic polysulfanes described are compounds of the type R-S(sub n)- R with n>2, which are chain-like or cyclic. Preparation structure, modern analysis, basic reactions, natural occurrence, biological activity and practical importance of organic polysulfanes with three or more neighboring sulphur atoms in a chain or ring are reviewed.

Hydrogen atom transfer (HAT) and electronic transfer (ET) occur for the oxidation of R-DMAs by dioxygen adducts. By theoretical considerations the comparison of the magnitude of the KIE inter versus intra is reported.

Methane is formed in methanogenic archaea by the reduction of methyl-coenzyme M(CH3-S-COM) with coenzyme B (HS-CoB) to CH4 and the heterodisulfide CoM-S-S-CoB. The combination of EPR and HYSCORE data proves that, in the MCR(sub red2) state, HS-COM is directly coordinated to the Ni(I) ion.

Subtle variations in the supramolecular organization of donor molecules charge-transfer salts of the organo-sulfur donor bis (ethylenedithio) tetrathiafulvalene (ET) have been found to promote most of the collective electronic ground states known to condensed matter science. It has been discovered that dramatic divergences between the low-temperature transport properties of two new ET charge transfer salts.