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A nanofabricated mechanically controllable break junction was used to fabricate Au-TTF-Au (tetrathiafulvalene, TTF) and Au-TSF-Au (tetraselenafulvalene, TSF) single-molecule junctions. The difference observed in single-molecule conductances of the two types of junctions originated from the difference in the strength of the molecule-electrode coupling through face-to-face overlapping configurations.

The article studies the iron-sulfur cluster of pyruvate formate-lyase activating enzyme (PFL-AE) in whole cells that undergoes cluster interconversion and a valence-localized in vitro, with only the [[4Fe-4S].sup.2+] cluster state. Findings reveal changes in cluster composition of PFL-AE in response to the redox state of the cell.

The tautomeric and recognition properties of thymine, 2- and 4-thioketothymines are analyzed by using accurate ab initio methods combined with molecular dynamics simulations and free energy calculations. The results have shown the complete tautomeric and recognition characteristics of thioketothymines and also that both 2-thioketo and 4-thioketothymine are excellent molecules for introducing special chemical properties in modified DNA.

A series of sulfuryl imidazolium salts (SISs) are prepared and examined as reagents for including trichloroethyl-protected sulfate esters into carbohydrates. Difficult O-sulfations that needed prolonged reaction times and a large excess of the SIS bearing of 1-methylimidazolium group (SIS 5) are achieved by using less than half the amount of 1,2-dimethylimidazolium moiety (SIS 9) and also N-sulfated compounds are obtained by using SIS 9.

The synthesis of a new series of electron donor-acceptor conjugates in which the electron acceptor-[C.sub.60]-and the electron donor-[pi]-extended tetrathiafulvalene (exTTF)-are bridged by using m-phenyleneethynylene spacers of variable length is described. AFM spectroscopy is used for showing the ability of these new conjugates to form wirelike structures upon deposition onto a mica surface.

The hydrolysis rate of the lipids is optimized along with the release profile of the drugs from the liposomes in order to prepare a thio-ester pro anticancer ether lipid. The studies have shown that the enzyme-catalyzed hydrolysis of thio-esters have followed a different pathway when compared to the hydrolysis pathway of the free thio-ester.

Several studies are conducted to explain the mechanisms associated with the catalytic enantioselective synthesis of [alpha],[beta]-diamino acid derivatives. The organocatalytic Mannich additions of [alpha]-isothiocyanato imides to sulfonyl imines are also studied.

The synthesis and structural characterization of a a dithieno[3,2-c:2',3'-e](1,2-dihydro-1,2-diborin) derivative and its dianion salts as a B-B bond-containing polycyclic [pi]-electron system. An intriguing countercation effect exhibited by the dianion salts on their photophysical properties indicated a possible electronic tuning by the countercations.

A novel combination of a molten globule-type C-terminal domain and an N-terminal domain with a fully folded regular tertiary structure possessed by human NFU also known as HIRIP5 implicated in cellular iron-sulfur cluster biosynthesis is described. Human NFU is found to be a functionally competent reducing agent for cysteinyl persulfide bond cleavage which release inorganic sulfide for incorporation into the ISU-bound [2Fe-2S] cluster, a reactivity that might be facilitated by the flexibility of the C-terminal domain.

benzothiadiazole derivatives (BH0-BH3), including two fluorene derivatives (AB2 and C01) is reported. The studied group was observed to show rare green photoluminescence ([[lambda].sub.PL] = 490-556 nm) with a high PL quantum efficiency in solution ([Phi] = 5 to 90%).

The product ratios are studied from the reductive cleavage of di-4-tolylethylsulfonium and di-4-tolyl-2-phenylethylsulfonium salts by a variety of one-electron reducing agents ranging in potential from -0.77 to +2.5 eV and including thermal reductants, indirect electrolyses mediated by a series of cyanoaromatics and excited singlet states. The differences between reductive cleavages of mono- and diarylsulfonium salts are direct consequences of the structures of the sulfuranyl radical intermediates and the bond dissociation energies of the alkyl and aryl bonds.

The preparation, analysis and carrier generation mechanism of self-doping in a tetrathiafulvalene (TTF) conductor, ammonium tetrathiafulvalene-2-carboxylate (TTFCO[O.sup.-]N[H.sub.4.sup.+]), are described along with molecular orbital characteristics. TTFCO[O.sup.-]N[H.sub.4.sup.+] is described as a 'hydrogen-bonding-assisted self-doped conductor' and the contribution of the hydrogen-bonding interaction to the electron conduction is supported by a large isotope effect in the ac conductivity.

The potential energy surfaces of the desulfinylation of prop-2-enesulfinic acid in C[H.sub.2][Cl.sub.2] solution are explored by using quantum calculations and are analyzed with kinetic data obtained for the reaction in absence or presence of additives. Experiments have shown that the thermodynamically unfavored ene reaction of S[O.sub.2] with propene has occurred at low temperature by using 1 equiv of B[F.sub.3].

A molecular imprinting method is applied for constructing prosthetic group-coupled tunable binding cavities for bisphenol A (BPA) and a novel template molecule is designed, with a structure consisting of BPA covalently conjugated with allyl(4-carboxyphenyl)disulfides through ester bonds (BPA-D). The noncovalent-type ion-paired cofactors are introduced when the two thiol groups in the apo-type cavities are oxidized to sulfonic acid groups and various prosthetic groups and cofactors are used for tuning binding properties of the holo-type cavities.

The highly enantioselective addition of thioacetic acid to nitroalkenes is described by using a new sulfinyl urea organocatalyst. The new method is used for preparing chiral 1,2-aminothiol derivatives, as shown by the first enantioselective synthesis of the clinically used antifungal drug sulconazole.

The exact stereochemical structures of kotalanol and de-O-sulfonated-kotalanol, which are used for the treatment of type-2 diabetes, are described by synthesis and comparison of their physical data to those of the corresponding natural compounds. The synthesis of kotalanol is achieved by coupling p-methoxybenzyl (PMP)-protected 4-thiol-D-arabinitol with a cyclic sulfate that is prepared from the naturally occurring D-perseitol.

A gene cluster responsible for thiostrepton biosynthesis and the encoded gene products are described. The analysis has shown that the thiopeptides are a type of bacteriocin, a family of genetically encoded antimicrobial peptides, and they are subjected to posttranslational modification during maturation of the prepeptide.

A simple and general method is developed for fabricating yolk/shell structures through a one-step encapsulation of particles by Si[O.sub.2] shells in aqueous mixtures of lauryl sulfonate betaine (LSB) and sodium dodecyl benzenesulfonate (SDBS). Various yolk/shell structures with different particles cores are also prepared.

Higher lipophilicity of perfluoroalkyl carboxylate and sulfonate in described in comparison to their alkyl counterparts. The high lipophilicity of perfluoroalkyl carboxylate and sulfonate has shown that their permeation across the thin lipophilic membrane as a bilayer lipid membrane is limited by their transfer at a membrane/water interface and the limiting permeability is lower and less dependent on their lipophilicity.

The traditional dye Thioflavin-T is used for designing new multifunctional molecules that contain both amyloid binding and metal chelating properties. The results have shown that the new multifunctional thioflavin-based chelating agents can be used as Alzheimer's disease therapeutics.

An endocyclic restriction test is used to study the trajectories for nucleophilic substitutions at sulfur(VI) and sulfur(II). The findings for the transition structures of sulfur transfer reactions provide insight into the large angle between the entering and leaving group, geometry analogous to apical group positions in trigonal bipyramidal transition states.

The first synthesis of (-)-ushikulide A is described, which has established its relative and absolute stereochemistry. The efficiency of the strategy is because of the utilization of alkenes and alkynes as orthogonally reactive surrogates for hydroxyl and carbonyl functionalities.

A promiscuous sulfatase activity in nucleotide phosphodiesterase/pyrophosphatase from Xanthomonas axonopodis (NPP) is measured. The results have shown that active site contacts to substrate oxygen atoms that has not contacted the [Zn.sup.2+] ions has played an vital role in defining the selectivity of the enzymes.

The studies have shown that metallothionein-based system is capable of selectively sensing and removing heavy metal contaminants in the presence of large concentrations of background ions and it is recycled by using solutions of inexpensive chemical chelators. This material is prepared by using chemistry that is independent of the protein sequence and it can be applied to the generation of hybrid materials with diverse binding capabilities.

A major simplification is described in the field of native chemical ligation (NCL). The feasibility of NCL with oxo- rather than thioesters is demonstrated by balancing acyl donor potential with substrate stability.

A layer-by-layer stepwise fabrication method is described for the construction and characterization of crystalline surface coordination polymers (SCPs). This method can be used for preparing Josephson junctions of superconductors, magnetic spin valves, capacitance, screen displays, fuel cells and catalytic devices.

A new method is developed for stereocontrolled glycosylation and chemoselective oligosaccharide synthesis. The oligosaccharide synthesis has shown that the strategy has provided trans-trans and trans-cis patterned oligosaccharides as opposed to classic Fraser-Reid's armed-disarmed approach leading to cis-trans and cis-cis linkages.

The [2,3]-sigmatropic rearrangement of a variety of configurationally stable diastereomeric allylic sulfinyl dihydropyrans, which are produced by base-promoted cyclization of sulfinyl dienols, is analyzed. This method is applied to the preparation of the cores of ent-dysiherbaine and deoxymalayamicin A by using efficient tethered aminohydroxylations.

A protocol is described for the elimination of [beta]-hydroxythioethers under Mitsunobu conditions for the olefination of propargylic dithioacetals with a carbonyl compound. The reaction could be considered as an alternative of McMurry-type coupling of two different carbonyl equivalents to obtain the corresponding olefins.

The density functional theory is used to examine the factors that control enantio- and diastereoselection in asymmetric aziridination reaction via the addition of chiral bicyclic sulfur ylides to substituted aldimines. The results showed that the diastereoselectivity with stabilized ylide could be influence by suitable modification of the N-substituent on the aldimine.