A sense of cell-being: Single-walled carbon nanotubes (SWNTs) are functionalized with bioactive monosaccharides to enable their use as biosensors. The glycosylated nanotube network is biocompatible and can interface with living cells (see scheme) to electronically detect biomolecular release with high temporal resolution and high sensitivity.

Carbon nanotubes (CNTs) have attracted tremendous attention in biomedical applications due to their molecular size and unique properties. This tutorial review summarizes the strategies to functionalize CNTs with bioactive carbohydrates, which improve their solubility, biocompatibility and biofunctionalities while preserving their desired properties. In addition, studies on the usage of carbohydrate functionalized CNTs to detect bacteria, to bind to specific lectins, to deliver glycomimetic drug molecules into cells and to probe cellular activities as biosensors are reviewed. Improvement in biocompatibility and introduction of bio-functionalities by integration of carbohydrate with CNTs are paving the way to glyconanotechnology and may provide new tools for glycobiological studies.

A highly efficient synthesis of L-ristosamine and L-epi-daunosamine glycosides via BF(3)·OEt(2) promoted tandem hydroamination/glycosylation of 3,4-di-O-acetyl-6-deoxy-L-glucal and L-galactal has been developed. The new method proceeds in a completely stereocontrolled manner within a short reaction time. Preparation of a library of L-ristosamine and L-epi-daunosamine glycosides with potential biochemical applications, by varying each component, exemplified the generality of the reaction.

A low-cost and highly sensitive biosensor system is designed to investigate carbohydrate-lectin interactions. This combination of glyco-gold nanoparticles and boronic acid biosensor system opens a way to study noncovalent drug delivery.

An organocatalytic intramolecular Stetter-type hydroacylation reaction between an aldehyde and an activated alkyne has been developed. This study induces salicylaldehyde-derived alkyne derivatives to assemble into a series of chromone derivatives using a catalytic amount of thiazoliumbased carbene catalyst.Keywords: chromones; hydroacylation; N-heterocyclic carbenes; organocatalysis; Stetter reaction Over the past few decades, the development of N-heterocyclic carbenes (NHC) has made important headways due to their extensive applicability in several reactions.[1] Besides the role as excellent ligands in the metal-catalyzed reactions, [2a-c] their ability to efficiently catalyze a number of organic reactions, most notably benzoin condensation, [2d-j] Stetter reaction, [3] transesterification [3h] and homo-enolate addition, [4] has contributed significantly to organic transformations. In 1973, Stetter established the first conjugate addition of aldehydes to a,b-unsaturated ester adopting the cyanide ion as the initial catalyst, [5a] and subsequently using a thiazolium-based carbene catalyst.[5b,c] The recent intermolecular variants of the Stetter reaction set in motion an expanding usage of NHCs as organocatalysts for carbon-carbon bond formation.[6] By exploiting an intramolecular Stetter reaction, Trost [7a] constructed a tricyclic system in order to synthesize hirsutic acid. Pioneering studies carried out by Ciganek, [7b] Enders [7c] and Rovis [7d,e] resulted in the development of intramolecular cyclizations as an access to various chromones. In addition, Glorius [8a,b] and She [8c] embarked on intramolecular acyl anion additions to unactivated olefin to construct the chromone scaffolds.Chromones are useful heterocyclic motifs found commonly in pharmaceutical compounds and they often exhibit fascinating therapeutic effects.[9] Our interest in drug discovery [10] motivated us to devise new methodologies for the chromone synthesis. Recently, we reported an NHC-catalyzed intramolecular crosscoupling between the aldehyde and the nitrile function to afford 3-aminochromones in high yields [11] [Scheme 1, Eq. (1)]. A comparison of this chemistry to that of the Stetter reaction [Scheme 1, Eq. (2)] prompted us to investigate the possibility of a newly designed carbon-carbon bond forming reaction Scheme 1. NHC-catalyzed C À C bond formation strategy.

Chemical C-glycosylation has been well developed to improve stereoselectivity in recent years. Due to its high efficiency to build C-glycosides or O-cyclic compounds, C-glycosylation has found widespread use in the synthesis of biologically active molecules. This review highlights the C-glycosylation methods that have been practised in the total synthesis of natural products and pharmaceuticals in the past decade.

A sense of cell‐being: Single‐walled carbon nanotubes (SWNTs) are functionalized with bioactive monosaccharides to enable their use as biosensors. The glycosylated nanotube network is biocompatible and can interface with living cells (see scheme) to electronically detect biomolecular release with high temporal resolution and high sensitivity.

Tamiflu is currently the most effective drug for the treatment of influenza, but the insufficient supply and side-effects of this drug demand urgent solutions. We present a practical synthesis of Tamiflu by using novel synthetic routes, cheap reagents, and the abundantly available starting material D-glucal. The strategy features a Claisen rearrangement of hexose to obtain the cyclohexene backbone and introduction of diamino groups through tandem intramolecular aziridination and ring opening. In addition, this synthetic protocol allows late-stage functionalization for the flexible synthesis of Tamiflu analogues. By using the synthesized Tamiflu and its active metabolite (oseltamivir carboxylate), we investigated their influences on neuroendocrine PC12 cells in various aspects. It was discovered that oseltamivir carboxylate significantly inhibits the vesicular exocytosis (regulated secretion) of PC12 cells, and suggests a mechanism underlying the Tamiflu side-effects, in particular its possible adverse influences on neurotransmitter release in the central nervous system.