"The α-amino acids, molecules of which have restricted conformational flexibility, are widely used in design of peptidomimetics, peptide models, and in systematic search for biologically active compounds. Among these amino acids, a distinct class of compounds can be highlighted, namely - conformationally rigid amino acids (CRA). Certain torsion angles, which describe the conformation of a polypeptide chain at the CRA, are "fixed" that allows predicting and controlling it to some extent. Many structural studies show that the CRA residues can dictate certain conformation of the peptide chain around them, consequently, they can stabilize or destabilize certain peptide secondary structure elements.

For Palladium-Catalysed C–N And C–C Cross-Couplings.

Air and moisture insensitive auxiliary ligands for highly efficient palladium catalysts. These ultra-low loading (high TONs or TOFs) catalysts have shown excellent activity in Suzuki cross-coupling with aryl bromides and chlorides, Heck vinylation, Heck-Sonogashira alkynylation and allylic amination of allyl acetates (Tsuji–Trost type reactions). Low loadings of the catalysts ensure minimal contamination of the final compounds with palladium and simplify the purification procedures. High stability of the allows to store them for unlimited time without special precautions.

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Recently 3-amino-tetrahydrothiophen-1,1-dioxides have drawn significant attention of a major drug developers. A few publications have been released earlier, corroborating rather high potential of this pharmacophoric moiety.

In the last decade, development of new drugs increasingly requires the use of chiral building blocks for hit-to-lead optimization, and even on early stages - in search for efficient hit compounds. The main fundamental reason for this lies in the fact that almost all the biological targets are chiral, and the drug-receptor interaction requires strict match of chirality. The formal reason results from strengthening the regulatory guidance for submitting new drug applications in Europe and USA which concern chirality issues.