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Abstract: A new methodology for determination of sulfonamides (sulfaquinoxaline, sulfathiazole, and sulfadimethoxine) in water samples was developed by coupling an automated multi-pumping flow system (MPFS) with a liquid waveguide capillary [...]

The structural and functional consequences of positively charged, negatively charged, and neutral groups incorporated at the para position of benzenesulfonamide carbonic anhydrase (CA) inhibitors are reported. The results have indicated that positively charged moieties should be avoided in the design of linker segments and such charges are more poorly tolerated by CA I when compared to CA II.

A series of 2-substituted derivatives of saccharin are prepared by using the N-cumylsulfonamide directed metalation group (DMG), according to the directed ortho metalation (DoM) tactic. It is seen that mild conditions for N-decumylation and other simple transformations of the products are achieved, 4,7- disubstituted saccharins are obtained and mild TFA-mediated N-decumylation yields substituted primary arylsulfonamides.

The radical cyclization reactions of unsaturated sulfonamides are examined along with the effect of halogen substitution. The vinylic halogen substitution has inhibited the competing ionic iodocyclization process to allow the radical cyclization to proceed smoothly and has also shown a remarkable effect in controlling the regioselectivity of cyclization.

Chiral (S)-tert-butanesulfinamide is used to synthesize a novel class of sulfinamido alcohol ligands. These ligands have displayed good catalytic activities and enantiomeric selectivities in asymmetric additions of diethylzinc to aromatic aldehydes.

The synthesis of 'designer' dendrimers and dendrons with sulfonlmide units at every branching point is reported. Two models branched oligosulfonimides are characterized in the solid state by single-crystal X-ray analysis and the reaction selectivities and conformation of sulfonimide branching points are rationalized by DFT calculations.

A new analogues of clavizepine that have no-ring-substitutents is synthesized. The very efficient key amination of an hydroxymethylxanthene intermediate by a Mitsunobu reaction using trifluoromethanesulfonamide allowed preparation of the tetracyclic chromeno-3-benzazepine in just six steps and 38% overall yield.

Molecular dynamics (MD) simulations using a many-body polarizable force field are performed on ethylene carbonate (EC) doped with lithium bistrifluoromethanesulfonamide (LiTFSI) salt as a function of temperature and salt concentration. The investigation of the Li(super +) transport mechanism has revealed that contribution from the Li(super +) diffusion together with its coordination shell to the total Li(super +) transport is similar to the contribution arising from Li(super +) exchanging solvent molecules in its first coordination shell with solvents from the outer shells.

The intermolecular hydroamination of 1,3-dienes with various carbamates, sulfonamides and carboxamides is catalyzed by the bismuth compound, Bi(Otf)(sub 3)/Cu(CH(sub 3)CN)(sub 4)PF(sub 6) to give out allylic amines in good yields. The compound used as a catalyst has proved to be of great help in the intermolecular hydroamination, as it also makes the study of the postulated reaction mechanism possible.

Heteroaromatic thiols might be oxidized to the sulfonyl chloride at low temperature by using 3.3 equiv of aqueous sodium hypochlorite and the reaction is rapid, avoids the use of chlorine gas, and succeeds with substrates that have previously been found to afford little or none of the sulfonamide product with other procedures. The method allows the preparation of the sulfonyl fluorides, which are stable enough to be purified and stored, making them potentially useful monomers in parallel chemistry efforts.

A study to determine the crystal structures of the [Cu(L(super 1))(sub 2)(NH(sub 3))(sub 2)].2MeOH (1), [Cu(L(super 2))(sub 2)(NH(sub 3))(sub 2)].2MeOH (2) and [Cu(L(super 3))(sub 2)(NH(sub 3))(sub 2)].2MeOH (3) is made. The results reveal that in compounds 1 and 2 the metal ion is coordinated by two benzothiazole N atoms from two sulfonamidate anions and two NH(sub 3) molecules while in compound 3 the metal ion is linked to benzothiazole N and sulfonamidate O atoms of one of the ligands, the benzothiazole N of another sulfonamidate anion and two ammonia N atoms.

Analogous transformations starting from the corresponding o-azidosulfonamides are reported that lead to a short and high yield route to 2-N-Alkyl derivatives is discussed. It is shown that primary sulfonamides undergo the same reaction opening up a new route to compounds of tautomeric form.

The o-phenylenediamine-derived disulfonamide ligands N,N'-Diphenyl-1,2-benzenedisulfonamide (1)and N,N'-Di-(4-tert-butylbenzene)-1,2-benzenedisulfonamide (2) complex and efficiently extract Pb(II) from water into 1,2-dichloroethane via ion-exchange, in combination with 2,2'-bipyridine. The corresponding Pb(II)-sulfonamido binary complexes of ligands 1 and 2 and ternary complexes with 2,2'-bipyridine are isolated and characterized.

We herein describe a novel palladium catalysed three-component cascade process involving carbonylation of an aryl iodide to generate an acyl palladium(II) species that is intercepted by a primary aliphatic or aromatic amine, amide, or sulfonamide followed by intramolecular Michael addition to furnish N-substituted isoindolinones in good yield. Overall, the cascade results in the formation of one C--C and two C--N bonds, one ring and one stereocentre. Key words: isoindolinone, palladium, cascade, amidation, sulfonamidation. On decrit un nouveau processus en cascade, a trois composants et catalyse par le palladium qui permet de proceder a la carbonylation d'un iodure d'aryle pour generer une espece palladium(II) acyle qui peut etre interceptee par une amine, un amide ou un sulfonamide primaire, aliphatique ou aromatique, suivie d'une addition intramoleculaire de Michael qui permet d'obtenir des isoindolinones N-substituees avec de bons rendements. La cascade globale conduit a la formation d'une liaison C--C et de deux liaisons C--N, d'un cycle et d'un stereocentre. Mots cles : isoindolinone, palladium, cascade, amidation, sulfonamidation. [Traduit par la Redaction]

Dinuclear copper(II) complexes with N-substituted ligands as superoxide dismutase (SOD) mimics are investigated. The new N-(thiazol-2-yl)toluenesulfonamide (Htz-tol) and N-(thiazol-2-yl)toluenesulfonamide (Htz-tol) and N-(thiazol-2-yl)naphthalene-sulfonamide (Htz-naf) ligands are prepared and structurally characterized.

An approach for the preparation of cyclic peptidosulfonamides through ring-closing metathesis is described. In this approach, amino acids can be attached to the cyclic peptidosulfonamide, which creates the possibilities of uniting this cyclic sulfonamide moiety in a peptide sequence.

Nitric Oxide plays an important role in many striking discoveries of wide human physiological processes. Experiments conducted on four substituted derivatives of Hantzsch 1,4 dihydropyridines were treated by nitric oxide (NO) or its donor N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS) to give the corresponding pyridine derivatives and its results are discussed.

A highly enantio- and diastereoselective anti-aldol process catalyzed by a proline mimetic, N-(dodecylphenylsulfonyl)-2-pyrrolidinecarboxamide, is developed. The studies have shown that the origins of enhanced diastereoselectivity are because of the presence of nonclassical hydrogen bonds between the sulfonamide, the electrophile, and the catalyst enamine that favor the major anti-Re aldol TS in the Houk-List model.

A room-temperature, copper-catalyzed amination of primary benzylic C-H bonds with primary and secondary sulfonamides was examined to determine the factors that influenced the selectivity of C-H functionalization between primary and secondary sites. The reaction could be applied to the coupling of a range of primary and secondary benzylic hydrocarbons with a diverse set of sulfonamides and is tolerant of substitution on both coupling partners.

The mechanism study of C-F reductive elimination from a transition metal complex and the evaluation of C-F bond formation from three Pd(IV) fluoride complexes are described. The ancillary pyridyl-sulfonamide ligand has played a main role for C-F reductive elimination in which an oxygen atom of the sulfonyl group has coordinated to Pd.

Highly regioselective metal-free oxidative cyclization of sulfonamides onto tethered, unactivated alkenes by using hypervalent iodine and Bronsted acids is described. The acid counterion is incorporated into the cyclized products in order to provide an overall aminotrifluoroacetoxylation of the alkene.

Application of [H.sub.2][O.sub.2] in conjunction with SO[Cl.sub.2] as a highly reactive reagent for the direct oxidative conversion of thiol derivatives to the corresponding sulfonyl chlorides with high purity through oxidative chlorination is described. The same reaction with amines could be used to generate corresponding sulfonamides in excellent yields within short duration of reaction times.

Several studies are conducted to explain the rational design of the highly enantioselective asymmetric Diels-Alder catalysts that are shown to be bearing several 4,4'-sulfonamidomethyl groups. The secondary reactions taking place in the system are shown to be extremely useful for high catalytic activity and high level of induction of enantioselectivity.

The various [beta]- and [alpha]-directing effects of the different groups of donors and acceptors present in mannipyranosylations are discussed. The strongly electron-withdrawing sulfonyl groups are shown to lead to higher stability of the triflates, as compared to the weak sulfonyl groups.

New tosyl derivatives of 2-iodylaniline and 2-iodylphenol are prepared by the dimethyldioxirane oxidation of the corresponding 2-iodophenyltosylamides or 2-iodophenyl tosylate and isolated as stable, microcrystalline products. Single-crystal X-ray diffraction analysis of N-(2-iodylphenyl)-N,4-dimethylbenzenesulfonamide has shown pseudocyclic structure formed by intramolecular IaO interactions between the hypervalent iodine center and the sulfonyl oxygens in the tosyl group.

Three distinct sites for structural modification have afforded access to a structurally diverse pool of chiral sulfonamides. The generality and effectiveness of the approach is shown by selecting five diverse C-C bond-forming cases from the halichondrin synthesis.

The applicability of the various tetrathiomolybdate mediated aziridine ring-opening reactions for the direct synthesis of the functionalized unsymmetrical [beta]-sulfonamido disulfides is discussed. The method is shown to be extremely beneficial, as it gives the product in high yields.

The synthesis of novel, red-shifted 8-hydroxyquinoline-based fluorophores and their incorporation into peptidyl kinase activity reporters is described. The result obtained demonstrated the extended utility range of kinase sensors that are based on chelation-enhanced fluorescence (CHEF).

The article presents a new methodology, which employs the copper-catalyzed domino three-component coupling-cyclization mechanism for the synthesis of a series of nitrogen heterocycles. The approach is shown to be useful for the synthesis of several other compounds, including polycyclic indoles as well.

Sulfonamide-resistant Escherichia coli and Salmonella isolates from pigs and chickens in Ontario and Quebec are screened for sul1, sul2 and sul3 by PCR. Each sul gene is distributed differently across populations, with a significant difference between distribution in commensal Escherichia coli and Salmonella isolates and sul3 restricted mainly to porcine Escherichia coli isolates.

The synthesis and activation kinetics with relevant activating agents for the model porphyrinic macrocycle compounds based upon meso-(p-aminophenyl)porphyrins bearing 1 to 4 sulfonamide-linked 2,4-dinitrobenzene are reported. The developed method to further modity the porphyrin in order to modulate the polarity and effect conjugation to biomolecules or nanoparticulate scaffolds could also be applied for the treatment of a number of disease states such as cancer and bacterial infection.

The first example of Hofmann rearrangement of primary arenesulfonamides is described that has depended on the utility of p-trifluoromethylphenyl(difluoro)-[[lambda].sup.3]-bromane and has produced N-arylsulfamoyl fluorides selectively at room temperature. The results obtained from the reaction of 2,3,5,6-tetramethylbenzenesulfonamide has shown that the generation of sulfonyl nitrene is not involved in this rearrangement.

Inhibitors based on p-aminobenzoylsulfonamide compounds and 1,3,4-thiadiazolylsulfonamides as well as amino acid activators were employed to study a small-molecule stabilization of the exceptionally destabilized human carbonic anhydrase II (HCA II) mutant H107Y. The findings from the study could be used to design small-molecule folding modulators and possibly autoactivatable molecules for suppression of misfolding of destabilized HCA II mutants which cause Marble brain disease (MBD).

The treatment of N-tosyl aldimines with dialkyl trimethylsilyl phosphites in the presence of iodine as a catalyst has produced the corresponding sulfonamide phosphonates.

Asymmetric V-catalyzed epoxidation of allylic alcohols are carried out in water with chiral ligands, which has incorporated sulfonamide and hydroxamic acid fragments. The reaction, notorious for its ligand-deceleration effect, in water has turned into the ligand-accelerated process.

The reaction of [[Cp*Rh[Cl.sub.2]].sub.2] (Cp* = [[eta].sup.5]-[C.sub.5][(C[H.sub.3]).sub.5]] with 2 equiv of p-toluenesulfonamide in the presence of KOH has formed the sulfonylimido-bridged dirhodium(III) complex. The redox interconversion between the sulfonylimido-bridged dirhodium(III) and sulfonylamido-bridged dirhodium(II) complex is applied to catalytic aerobic oxidation of [H.sub.2] and an alcohol by using sulfonylimido-bridged dirhodium(III) as a well-defined dinuclear catalyst.

The addition of elemental bromide dissolved in C[H.sub.2][Cl.sub.2] to para-disubstituted benzodiaocines, where X is the same (H, C[H.sub.3], Br, OMe, N[O.sub.2]) or a different substituent as X and Y (C[H.sub.3], Br; OMe, N[O.sub.2]) has proceeded with competition between two pathways. The regio- and stereoselectivities have established the capability of sulfonamide nitrogen centers to engage in neighboring group participation.

The synthesis of S-glycosyl sulfonamides wherein the primary sulfonamide functional group (-S[O.sub.2]N[H.sub.2]) is attached to the anomeric position of a carbohydrate moiety is described. The general method consists of first introducing a thioacetate group at the anomeric center of a per-O-acetylated sugar derivative and a variety of mono- and disaccharide derivatives are prepared using this new methodology.

Ytterbium(III) triflate-catalyzed ring opening of substituted 1-cyclopropyl-2-propyn-1-ols with sulfonamdies as an efficient route to conjugated enynes is described. The reaction is operationally straightforward and is accomplished in regioselective manner in all except one case under mild conditions.

The development of a new magnetite-immobilized nano-Ru catalyst for the environmentally benign synthesis of sulfonamides and alcohols is described. The results revealed that heterogeneous catalyst has catalyzed the underlying C-N bond formation reaction of sulfonamides with alcohols via a domino dehydrogenation-coupling-hydrogenation mechanism.