The Claisen rearrangement and its applications to organic synthesis have been studied for a long time.l In recent years, this rearrangement has been applied in stereocontrolled natural product synthesis2 and asymmetric i n d ~ c t i o n . ~ The term "Claisen rearrangement", which originally denoted the rearrangement of allyl aryl ethers to 0or p-allylphenols, has now been extended to analogous ...

Streptomyces lavendulae produces complestatin, a cyclic peptide natural product that antagonizes pharmacologically relevant protein-protein interactions including formation of the C4b,2b complex in the complement cascade and gp120-CD4 binding in the HIV life cycle. Complestatin, a member of the vancomycin group of natural products, consists of an alpha-ketoacyl hexapeptide backbone modified by ...

The cleavage of C−O linkages in aryl ethers biomass-derived lignin compounds without hydrogenation the aromatic rings is a major challenge for production sustainable mono-aromatics. Conventional strategies over heterogeneous metal catalysts require addition homogeneous base additives causing environmental problems. Herein, we propose Ru/C catalyst modified by Br atoms selective direct bonds dip...

Amino acids are important biomolecules with a broad scope of applications in chemical and biological sciences. Their functions properties depend on their absolute configuration. Therefore, methods for chiral recognition separation amino highly sought after. For the purposes diagnostic medicinal water is particularly relevant. However synthetic receptors enantioselective binding aqueous media ra...

An alternative green method was developed for the synthesis of thio- and selenoflavones by ring closure 2-chlorophenyl ethynyl ketone with NaHY (Y = S, Se). These nucleophilic chalcogen species were generated in situ using NaBH4 to reduce elemental presence polyethylene glycol-400 (PEG-400). The efficiency this reaction is strongly dependent on PEG-400 solvent, acting like a crown ether, comple...