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The use of N-acyl oxazolidinones as a viable solution for promoting acyl-like radical couplings with both problematic amino acids and alpha-substituted acrylates and acrylamides is reported. A convenient two-step procedure is devised for the preparation of N-acyl oxazolidinones of N-protected amino acids, which provides consistently good yields of the corresponding imide.

The development of a stereodivergent base-promoted strategy to access both cis- and trans-carbomethoxy oxazolidin-2-one-intermediates is reported. It shows that the stereochemical outcome of the base-catalyzed epimerization of ester-substituted oxazolidinones could be effectively controlled using selective protonation agents.

The kinetic resolution of chiral 2-oxazolidinones through catalytic, which was achieved by highly enantio-selective N-acylation is presented. The findings provide data for the exploration of enantioselective N-acylation of other classes of chiral secondary amides.

A novel and simple procedure to prepare 2,4,5-trisubstituted 1,3-oxazoles is reported. The proposed method for the formation of oxazoles involves an unstable 1-(methylthio)-2-oxopropyl triflate, which was detected from the low-temperature NMR spectra.

Novel phosphinooxazolines, containing a unit of central and a unit of planar chirality in a matched case combination and a ferrocene backbone are synthesized and studied. They are successfully tested in the Pd-catalyzed asymmetric allelic substitution with cycloalkenyl acetates as substrates.

The studies performed with chiral oxazolines as vehicles for a number of carbon--carbon bond-forming reactions are traced back to the early 1970s, where the main source of chirality was derived from chiral, and nonracemic amino alcohols. The factors responsible for high optical yields during that era were attributed to rigidity or precomplexation of the reactants, thus providing a more well-defined topograhy during the reaction course.

A one-pot synthesis of 2,4,5-trisubtituted oxazoles via a Friedel-Crafts/Robinson-Gabriel synthesis using a general oxazolone template is reported. It is observed that treatment of the oxazolone template with a range of aromatic nucleophiles provides the highly substituted oxazoles in good yields.

An efficient synthesis of the C20-C32 segment of the phorboxazoles is achieved using an enantioselecttive hetero Diels-Alder reaction catalyzed by Jacobsen's Cr(III) amino indanol Schiff base catalyst. The synthesis was completed in 7 steps with a 20% overall yield from readily available starting materials.

C2-symmetric tridentate bis(oxazoline) and bis(thiazoline) ligands with a diphenylamine backbone are investigated in the catalytic asymmetric Henry reaction of alpha-keto esters with different Lewis acids. The results show that the NH group in C2-symmetric tridentate chiral ligands plays a very important role in controlling both the yields and enantiofacial selectivity of the Henry products.

A first complete series of racemic and enantiopure conducting salts are synthesized and characterized with metallic character, based on chiral oxazolines. Despite strongly related crystalline and electronic structures, the higher conductivity of pure enantiomers, lacking the disorder inherent to racemic mixture, demonstrates that the chiral donor route is very promising for the elaboration of other metallic salts.

The reaction between different metallocenes as a means of achieving the first highly enantioselective synthesis of planar chiral phosphapalladacycles is discussed. Chiral phosphpalladacycles are available in high enantioselectivity by utilizing oxazolines as recoverable palladium transfer reagents.

A short and efficient synthesis of homopentafluorophenylalanine from oxazolidine aldehyde in 57% overall yield is presented. The construction of 2R-homo-Pf-Phe is similarly achieved from the corresponding oxazolidine aldehyde derived from l-serine.

A study of the chemical stability of the oxazolidine linker system was carried out using a dual-linker analytical construct within a parallel reaction scan. The utility of oxazolidine aldehyde as a step in asymmetric chemistry was established by the solid-phase synthesis of a small molecular array while exploiting the data generated by the reaction scan.

The enantiomeric recognition of alpha-chiral primary ammonium ions has been studied with benzene-based tripodal tris(oxazoline) receptors. A good level of chiral discrimination is observed with one of the tripodal receptors, which provides a C3-symmetric chiral environment on guest binding.

The place of oxazolines in modern day chemistry is certainly self-evident. They are used in the development of chiral ligands used for asymmetric catalysis, which are found in natural products, and are used in synthesis and provide a useful means for the protection of amino alcohols or carboxylic acids.

Mechanistic evidence is presented that has supported the involvement of a ring-opening mechanism in the Pd-catalyzed direct arylation of benzoxazoles. The density functional theory (DFT) analysis has pointed that the direct arylation of benzoxazoles is an inherently facile process and that the control of substrate C-H acidity is the main element in developing a mild arylation protocol with the potential to accommodate a variety of electron-deficient substrates.

A novel intermolecular ene reaction using oxazolones and enol ethers are described under very mild reaction conditions. Results suggest that the transformation of the reaction on the whole complements the intramolecular Conia-ene cyclization and makes ene reactions a useful substitute to enolate alkylation chemistry.

A solution to the problems involving the preparation of family of isonitriles which have versatile functionality in organic synthesis is presented. Oxazoles were used to synthesize unsaturated isonitrile derivatives which include the ester functionality, pleasant organoleptic properties to organic compounds.

The bisoxazolidine ligand is prepared and its usefulness for asymmetric catalysis is shown. The bisoxazolidine ligand is successfully applied in the catalytic enantioselective alkynylation of a range of aromatic and aliphatic aldehydes generating chiral propargylic alcohol in high yields and enantioselectivities.

Protein identification in proteomics is mostly achieved by tandem mass spectrometry (MS/MS) analysis of peptides produced by enzymatic digestion. In the MS/MS experiments, protonated peptides undergo collision-induced dissociation (CID), and the fragment ion spectrum is used to assign their amino acid sequence.

A method for the direct stereoselective preparation of oxazines under mild conditions based on an unprecedented Lewis acid-promoted hetero-cope rearrangement is described. The process features the first examples of the [3,3]-sigmatropic rearrangement involving the nitroso group promoted by Lewis acid coordination.