Supramolecular fishing for plasma membrane proteins using an ultrastable synthetic host-guest binding pair.

Membrane proteomics, the large-scale global analysis of membrane proteins, is often constrained by the efficiency of separating and extracting membrane proteins. Recent approaches involve conjugating membrane proteins with the small molecule biotin and using the receptor streptavidin to extract the labelled proteins. Despite the many advantages of this method, several shortcomings remain, including potential contamination by endogenously biotinylated molecules and interference by streptavidin during analytical stages.

Synthesis of 2-deoxy cyclic and linear oligosaccharides by oligomerization of monomers.

Cyclic and linear oligosaccharides constituted with 2-deoxy sugar units are synthesized by an oligomerization reaction involving activated thioglycoside monomers, consisting of a 2-deoxy sugar unit. The oligomerization promoter plays an important role in the formation of either the cyclic- or the linear oligosaccharides. Encapsulation abilities of a 2-deoxy cyclic hexamer with p-nitrophenol, by a (1)H NMR method, showed complexation of the guest molecule with the host molecule.

Synthesis of 2-deoxy-D-arabino/lyxo-hexopyranosyl disaccharides.

Synthesis of 2-deoxy-D-arabino/lyxo-hexopyranosyl disaccharides is reported. In these, the disaccharides contain 2-deoxy-arabino-hexopyranosyl and 2-deoxy-lyxo-hexopyranosyl sugars as either the reducing or the non-reducing or both the sugar units of the disaccharides. The activated 2-deoxy-1-thioglycosides served as the common precursors to prepare the 2-deoxy disaccharides with the above configurations.

Synthesis of aryl-2-deoxy-D-lyxo/arabino-hexopyranosides from 2-deoxy-1-thioglycosides.

The synthesis of either anomers of aryl 2-deoxy-D-glycopyranosides from 2-deoxy-1-thioglycosides is reported. The alpha-anomers form as the major product when thioglycosides react with differently substituted phenols and naphthols, in the presence of N-iodosuccinimide/triflic acid. On the other hand, reaction of the thioglycosides with bromine initially, followed by reaction with aryloxy anions lead to aryl 2-deoxy-beta-D-glycosides with high specificities.

Catalytic ceric ammonium nitrate mediated synthesis of 2-deoxy-1-thioglycosides.

Synthesis of 2-deoxy-1-thioglycosides from glycals, mediated by catalytic amounts of ceric ammonium nitrate is reported. Apart from the 2-deoxy-1-thioglycosides, formation of the 2,3-unsaturated enose, corresponding to the Ferrier product, is also observed, especially for the glucal substrates. A radical oxocarbenium ion and a thiolate intermediates are most likely to mediate the reaction.