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One-electron reduction of methanesulfonyl chloride in the presence or in the absence of oxygen and the ability of MeS[O.sub.2.sup..] radical to act as oxidant and as catalyst in the cis-trans isomerization of unsaturated fatty acids is described. Unambiguous evidence is provided for a long-lived electron adduct to sulfonyl chlorides, which has acted as reductant and has established equilibrium with [O.sub.2.sup..-].

Beta-sultams are the sulfonyl analogues of beta-lactams and N-acyl beta-sultams are novel inactivators of the class C beta-lactamase of Enterobacter cloacae P99. The analogous N-acyl beta-lactams undergo enzyme-catalyzed hydrolysis, the rate of which is compatible with significant amide anion expulsion/S-N fission in the transition state, and the enzyme reaction displays a later transition compared with hydrogen-ion-catalyzed hydrolysis of the beta-sultam.

The UV-vis spectroscopy technique is employed to explain the mechanisms involved in the reactions of stabilized and semistabilized sulfur ylides with benzhydrylium ions. The various advantages and issues related to the application of sulfur ylides for the purpose of cyclopropanations are explained.

Several first-principles bottom-up investigations of the TTTA (1,3,5-trithia-2,4,6-triazapentalenyl) crystal are conducted to explain the magnetic bistability exhibited by the molecule-based magnets. The observed bistability is shown to be a result of the coexistence of monoclinic high temperature and triclinic low temperature phases.

The article explains the synthesis of an unprecedented luminescent polynuclear gold (I) [[mu].sub.3]-sulfido cluster, which is shown to exhibit a thiacrown-like architecture. The addition of [CH.sub.3]CN compound is shown to lead to numerous binding and spectroscopic changes in the system.

The functional characterization of a novel protein NosA in nosiheptide biosynthesis has provided an unusual C-terminal amide forming strategy in general for maturing certain amide-terminated thiopeptides by processing their precursor peptides featuring a serine extension. NosA has acted as an intermediate bearing a bis-dehydroalanine tail and has catalyzed an enamide dealkylation to remove the acrylate unit originating from the extended serine residue.

The first mechanistic insight into 2-thiosugar production in an angucycline-type antibiotic, BE-7585A, is reported. The results indicated that the sulfur insertion mechanism in 2-thiosugar biosynthesis shares similarities with that for thiamin biosynthesis.

A newly developed amino-thiocarbamate-catalyzed bromolactonization of unsaturated carboxylic acids is described. The newly developed protocol could be applied in the enantioselective synthesis of the key intermediates of VLA-4 antagonists.

A highly efficient and convenient strategy is described that has allowed rapid construction of unique optically active spiro[oxazoline-3,3' -oxindole]s through the organocatalyzed asymmetric synthesis of spirocyclic thiocarbamates via an aldol reaction. The evaluation of the spirooxazolines using a model of acute neuroinflammation has shown antipyretic activity and has provided an opportunity to discover new antipyretic agents.

Linear conjugated guest molecules with high aspect ratios have formed inclusion compounds with guanidinium organodisulfonate (GDS) host frameworks in which organodisulfonate ' pillars' have connected opposing GS sheets to generate lamellar architectures that reflect templating by the guest. The effects of the different framework architectures and packing motifs are marked as bathochromic shifts in the absorption and emission spectra of the guest when compared with their spectra in methanol solutions.

A novel polyketide metabolite, thailandamide lactone, which is not detected in the wild type, is isolated from the mutant broth, and its structure is analyzed by high-resolution mass spectrometry and IR and NMR spectroscopy. In a biological assay tumor cell lines, thialandamide lactone has displayed moderate antiproliferative activities.

Benzothiazinones (BTZs) have formed a new class of potent antimycobacterial agents. BTZs are activated in the bacterium by reduction of an essential nitro group to a nitroso derivative, which has reacted with a cysteine residue in the active site of decaprenylphosphoryl-[beta]-D-ribose 2E-epimerase (DprE1) of Mycobacterium tuberculosis.

G enetic i nterception and s tructural c haracterization of t hiopeptide c yclization p recursors for thiocillins (tclM) from Bacillus cereus is described. The studies provide insight into the TclM and its homologues in other thiazolyl peptide producing strains as the enzymes reponsible for the trans-annular heteroannulation at core of this class of molecules.

The application of the lissamine rhodamine B sulfonyl azide as an effective reagent for the detection of different protein thiocarboxylates in the bacterial proteome is discussed.

The article explains a new discrete solid-state process, which demonstrates the transfer of sulfur atoms between different crystal molecules.

The article presents a new approach, which can be employed for the Fmoc-based solid-phase synthesis of different peptide thioesters with self-purification facility. The application of these thioesters in the formation of several immobilized SH3 domains is also analyzed.

The article explains the various mechanisms involved in the chemoselective peptidomimetic ligation that takes place via the application of different thioacid peptides and aziridine-terminated templates and peptides. The process is shown to be applicable to a large number of unnatural amino acid residues.

The formation of micelles from a tetrathiafulvalene (TTF) end-functionalized poly(N-isopropylacrylamide) (poly(NIPAM)) derivative is described. The studies have shown that the chemical oxidation and complexation properties of the TTF unit are used for disrupting the micelle architecture to release the hydrophobic dye Nile Red from the interior of the micelle.

The pyrene-containing water-soluble nanoparticle is under electrostatic stress when diluted below the CMC of the surfactant and extremely rapid release of the hydrophobic content is observed when the cross-linker is cleaved. The method has combined the ease of physical entrapment and the precision of chemical ligation and is useful in the delivery and controlled release of pharmaceutical agents.

A new n-channel semiconductor class is described for organic field-effect transistors (OFETs) based on thienoquinoidal structures. Solution-processed FETs based on the terthienoquinoid derivative with ((n-alkyloxy)carbonyl)cyanomethylene moieties have displayed good electron mobilities under ambient conditions.

Direct catalytic asymmetric conjugate addition of terminal alkynes to [alpha],[beta]-unsaturated thioamides is described under proton transfer conditions. The intermediate copper thioamide enolate has worked as Bronsted base to drive the catalytic cycle via proton transfer and the divergent transformation of the thioamide functionality has highlighted the synthetic utility of the alkynylation products.

Experimental and theoretical studies were conducted to probe single-molecule conductances in phenylene-ethynylene molecules terminated with thiol and carbodithioate linkers. The results offer insight into the significant role for carbodithioate-based connectivity in molecular-scale electronics applications involving metallic and semiconducting electrodes.

An electrochemical STM setup was employed to study the electron transport characteristics in redox molecule-modified tunneling junctions Au(111)/6-thiohexanoylferrocene (Fc6)/solution gap/Au STM tip in the absence and in the presence of gold nanoclusters. The results demonstrated the power of the electrochemical approach in molecular electronics and offered a new perspective toward two-state and multistate electronic switching in condensed media at room temperature.

A highly regioselective 1,3-dipolar cycloadditions of exTTF-containing azomethine ylides to the endofullerene was performed to synthesize the stable donor-acceptor conjugates involving an endohedral metallofullerene, [La.sub.2]@[I.sub.h]-[C.sub.80], and [pi]-extended tetrathiafulvalene (exTTF). The results provide insight into the redox active character of the system due to the presence of both donor and acceptor groups and the electrochemically reversible character of the endofullerene which confirms the presence of the [5,6] adduct.

Prepeptide gene variants were introduced into a knockout strain to conduct an alanine scan C-terminal 14 residues of a 52-mer prepeptide which is converted by Bacillus cereus ATCC 14579 as well as a serine scan of the six cysteine residues that are converted to thiazoles in the mature natural product. The tight conformational rigidity of the natural product which is severely disrupted by loss of even a single heterocycle accounted for the attendant loss of activity in such mutants.

Structural analysis and genetic and biochemical experiments were performed for BE-7585A produced by Amycolatopsis orientalis subsp. vinearia BA-07585 which has a 2-thiosugar and is a member of the angucycline class of compounds. The spectroscopic analyses verified the structure of BE-7585A to be closely related to rhodonocardin A and provided insight into the biosynthetic pathway for BE-7585A which could be applied for future biochemical studies of 2-thiosugar biosynthesis and BE-7585A assembly.

The preparation and characterization of the long-sought parent oxathiirane from sulfine through photochemical rearrangement with light at [lambda] = 313 [plusmn] 10 nm in an Ar matrix at 11 K. The stability ordering and the relative energy differences of carbonyl versus thiocarbonyl groups underline the possible contibution of oxathiiranes in sulfur transfer reactions.

Ribosomally produced thiopeptide antibiotics are promising lead compounds targeting the GTPase-associated region (GAR) of the bacterial ribosome. The studies have shown that mutations of the L11 protein do not counteract binding of bicyclic thiopeptides, but has allowed the ribosome to bypass the protein biosynthesis blockade enforced by these antibiotics in the wild type.

The preformed tetrathiafulvalene (TTF) particles and 7,7'-8,8'-tetracyanoquinodimethane (TCNQ) microstructures are used for demonstrating the postchemistry of organic particles in aqueous solution. The TTF-TCNQ nanowires have displayed stable performance in organic nonvolatile memory devices with multiple write-read-erase-read cycles in air.

The recombinant proteins from Mycobacterium smegmatis are used to identify the ergothioneine biosynthetic gene cluster from mycobacteria and in vitro reconstitution of biosynthetic process. The findings indicated that ergothioneine productions are a frequent trait among fungi, actinobacteria, and cyanobacteria but also occurs in numerous bacteroidetes and proteobacteria.

A method is developed for identifying cysteine (Cys) residues with sulfhydryl (SH) groups displaying slow hydrogen exchange rates for proteins in aqueous media, where the method has used the isotope shifts of the [C.sub.[beta]] chemical shifts induced by the deuteration of the SH groups. The proton NOEs of the two slowly exchanging SH-s are identified in the NOESY spectra and are used for determining the local structure of Escherichia coli peptidyl prolyl cis-trans isomerase b (EPPIb) around Cys residues.

Colloidal quantum dot solar cells are fabricated under ambient atmosphere with an active area that has displayed 3.6% solar power conversion efficiency. A novel ligand strategy is described in which the quantum dots are encapsulated in the solution phase with the help of a strongly bound N-2,4,6-trimethylphenyl-N-methyldithiocarbamate ligand.

A chiral Kagome network is prepared at an aqueous solution/Au(111) interface by using a complicated stereo supramolecule thiacalix[4]arene tetrasulfonate as a building block. This has helped in constructing a 2D nanoporous network by various functional supramolecules and has shown potential application in host-guest chemistry as well as chiral resolution.

The new sulfur-containing clusterfullerenes [M.sub.2]S@[C.sub.82]-[C.sub.3v](8) are isolated for a variety of metals. Molecular dynamics simulations have shown that [Sc.sub.2]S cluster has displayed an almost free rotation around the [C.sub.3] axis of the carbon cage, which has resulted in a single line [super 45]Sc NMR spectrum.

The synthesis and characterization of four ladder-type oligo-p-phenylene containing donor-acceptor copolymers are described. The ladder-type oligo-p-phenylene is used as an electron donot unit in the copolymers to provide a deeper highest occupied molecular orbital (HOMO) level for obtaining polymer solar cells with a higher open-circuit voltage, while 4,7-dithien-2-yl-2,1,3-benzothiadiazole of 5,8-dithien-2-yl-2,3-diphenylquinoxaline is chosen as an electron acceptor unit to tube the electronic band gaps of the polymers for a better light harvesting ability.

A receptor is described for fullerenes featuring three exTTF units linked to a CTV scaffold. The exTTF-CTV host forms stable complexes with both [C.sub.60] and [C.sub.70] and light-induced ESR spectra have shown that intracomplex PET processes take place in solution.

The new semiconducting thiophosphate compounds KZrP[S.sub.6], RbZrP[S.sub.6] and CsZrP[S.sub.6] has displayed red light emission at room temperature. The materials have longer photoluminescence lifetimes than most of the inorganic chalcogenide semiconductors, which can be solution processed into thin films for potential device fabrication.

The design and synthesis of a new low-band-gap thieno[3,4-c]pyrrole-4,6-dione-based copolymer (PBDTTPD) is described. The polymer when blended with P[C.sub.71BM has shown a power conversion efficiency of 5.5% in a bulk-heterojunction photovoltaic device having an active area of 1.0 [cm.sup.2].

The development of metal-free organic sensitizers is very important in dye-sensitized solar cells and photovoltaic conversion with a new class of stable tetrathiafulvalene derivatives has shown electrochemical and kinetic properties. The proof-of-concept has shown that sensitizers with a small driving force has operated functionally in dye-sensitized solar cells and has helped in reducing photovoltage losses due to poor energetic alignment of the materials.

A method is developed for catalytic asymmetric [gamma] sulfenylation of carbonyl compounds. Sulfur nucleophiles are added to the three families of nucleophiles, which are shown to participate in catalyzed [gamma] additions.

A new [C.sub.2]-symmetric chiral bis-sulfoxide ligand, (R,R)-1,2-bis(tert-butylsulfinyl)benzene, is designed and prepared by the reaction of (R)-benzyl tert-butylsulfoxide with (R)-thiosulfinate. The ligand has displayed excellent enantioselectivities in the Rh-catalyzed asymmetric 1,4-addition reaction and the access to optically pure flavanones is realized via 1,4-addition of arylboronic reagents to chromenones.

Quantum dots (QDs) capped with bidentate zwitterionic dihydrolipoic acid-sulfobetaine (DHLA-SB) ligands are an alternative to polyethylene glycol-coated nanoparticles as they combine small sizes, low nonspecific adsorption, preserved optical properties and excellent stability over time and a wide range of pH and salinity. Streptavidin-functionalized DHLA-SB QDs are applied to track the intracellular recycling of cannabinoid receptor 1 (CB1R) in live cells.

A spin-polarized donor (BTBN) is prepared that is a dibromotetrathiafulvalene derivative containing a nitronyl nitroxide group in a cross-conjugated manner. The results have shown that the transport of carriers in the neutral unicomponent radical crystal is controlled by the external magnetic field, which are important for developing molecule-based spin electronic devices.

A unique approach is reported for the catalytic kinetic resolution of amine derivatives based on formamide and thioformamide substrates. The experiments have established a higher level of reactivity for thioformamide substrates than for their formamide analogues and the products of the asymmetric reactions are converted to desirable building blocks such as N-Boc-amines and the parent chiral formamide compounds.

Convergent synthesis of (-)-crambidine is described. The sequence has capitalized on two novel key transformations, which has included a [4+2] annulation of thiomidates with vinyl carbodiimides and an alkyne hydroamination using 2-aminopyrimidine nucleophiles.

A noncovalent interaction of thioflavin T (ThT), a fibril diagnostic dye, with the versatile macrocyclic host molecule cucurbit[7]uril (CB7) in the presence of metal cations is described. The usefulness of the supramolecular capsule is highlighted by demonstrating the rupture of the capsular complex with a strong competitive guest, 1-amantadine hydrochloride, which has helped in disrupting the capsule to release the dye.

A combination of substituent effects is used for describing the design, synthesis, isolation and characterization of the first persistent nonacene derivative. The powerful substituent effects are suitable for preparing other persistent, soluble, large acene derivatives needed for advanced thin-film organic semiconductor applications.

The first report on a multiconfigurational reference second-order perturbation theory-molecular mechanics study of the color modulation of the observed bioluminescence of the oxyluciferin-luciferase complex of the Japanese genji-botaru firefly are presented. The theoretical results which are in agreement with experimental observations indicated that the wavelength of the emitted light depends on the polarity of the microenvironment at the phenol/phenolate terminal of the benzothiazole fragment in oxyluciferin.

Several studies are conducted to explain the properties and differentiation of the numerous carbapenems, a clinically significant antibiotic family. The natural structural diversity observed in these antibiotics is shown to be highly dependent on the non-heme iron oxygenases.

Direct catalytic asymmetric aldol reaction of thioamides with a soft Lewis acid/hard Bronsted base cooperative catalytic system comprising (R,R)-Ph-BPE/[Cu[(C[H.sub.3]CN).sub.4]]P[F.sub.6]/LiOAr is described. Facile reduction of the thioamide functionality and a catalyst-controlled second aldol reaction has provided 1,3-diols in a highly stereoselective manner.