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An iodocyclization of sulfinimine-derived enantiopure homoallylic sulfonamides that represents a valuable new route for the asymmetric synthesis of trans-2,5-disubstituted pyrrolidines is described. The homoallylic sulfonamides were prepared from readily available sulfinimine-derived beta-amino aldehydes using the Wittig reaction and were obtained as E:Z mixtures.

Enantiopure aromatic (phenyl, naphthyl) and heteroaromatic (pyridyl, quinolyl, diazinyl) sulfoxides are synthesized by reaction of (S)-tert-butyl tert-butanethiosulfinate with aryl- or heteroaryllithium derivatives. An application of an enantiopure aminosulfoxide as N,S ligand for the asymmetric catalysis of allylic nucleophilic substitution is successfully tested.

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.

A general and efficient method is described for preparing 2,4-di- and trisubstituted thiazoles through p-TsOH.[H.sub.2]O-catalyzed cyclization of trisubstituted propargylic alcohols with thioamides. The reaction is achieved in under mild conditions that has not required the exclusion of air and moisture and has provided a convenient route to the synthetically useful aromatic heterocycle.

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.

Novel N-(Cbz-aminoacyl)thiosemicarbazides are cyclized by treatment with sulfuric acid to produce 1,3,4-thiadiazoles. These compounds have reacted with N-(Cbz-aminoacyl)- and - dipeptidoylbenzotriazoles to produce chirally pure 1,3,4-thiadiazol-2-yl-substituted amino acids and dipeptides.

Aziridinemethanol sulfonate esters have reacted with tetrathiomolybdate to produce thiirane derivatives as the major product and cyclic disulfides as minor product under mild reaction conditions via an unprecedented thia-aza-Payne-type rearrangement. It is shown that when the reaction of tetrathiomolybdate is carried out with 2-aziridino-cyclohexanol derivatives it has resulted in the formation of thia-bicyclo[3.1.1]heptane or dithia-bicyclo[3.2.1]octane derivatives.

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.

Ureas and thioureas derived from L- or D-valine have acted as bifunctional organocatalysts able to induce the enantioselective alcoholysis of mono-, bi- and tricyclic meso anhydrides. Both enantiomers of the hemiesters are obtained by changing the configuration of the catalyst.

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.

Cyclic cis-[beta]-amino Weinreb amides are prepared by ring-closing metathesis of sulfinimine-derived N-sulfinyl [beta]-amino diene Weinreb amides. The unsaturated cyclic cis-[beta]-amino Weinreb amides are useful for the asymmetric synthesis of cyclic-[beta]-amino acid derivatives.

Sulfinyl dienynes have undergone thermal and catalyzed IMDA cycloadditions to produce cyclohexa-1,4-dienes with high selectivities. The products have preserved synthetically useful vinyl sulfoxide functionality and the selective manipulation of the double bonds in the cycloadducts is examined.

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.

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.

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.