Perspective

Claus Jacob and colleagues at the University of Saarland in Germany review the chemistry behind the bioactivity of natural products in garlic. Long used as a natural remedy against various human illnesses, the antibiotic activity of garlic has mostly been associated with the thiosulfinate allicin. But recent studies have pointed towards a significant biological activity of trisulfides and tetrasulfides found in various Allium species, including a wide range of antibiotic properties and the ability of polysulfides to cause the death of certain cancer cells.




Emerging Area

The tandem reactions of salicylic aldehydes or salicylic imines with ,alpha,beta-unsaturated compounds is reviewed in an Emerging Area by Yong-Ling Shi and Min Shiat the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences. These tandem reactions provide an easy access to a variety of heterocycles, such as chromanes, chromenes, coumarins and tetrahydroxanthenones, many of which are synthetic useful intermediates.




Hot article

Frank Volz and Norbert Krause at the University of Dortmund in Germany exploit gold catalysts in natural product synthesis. The first enantioselective total syntheses of the -carboline alkaloids (-)-isochrysotricine (1) and (-)-isocyclocapitelline (2) are reported, confirming the absolute configuration of these natural products.  The key step is a gold-catalyzed, chirality-transferring allene cycloisomerization.




Hot article

Sabrina Göhler and Christian Stark from the Free University Berlin report a ruthenium tetroxide-catalyzed oxidative mono-cyclization of 1,5,9-trienes and polyenes. The poly-unsaturated substrates undergo mono-cyclization with a high degree of diastereo- and positionselectivity to produce mono-tetrahydrofuran diols with a varying degree of unsaturation, with up to four new stereogenic centres created in a single step.




On the front cover

Novel template-assembled oligosaccharide clusters as epitope mimics for HIV-neutralizing antibody 2G12 are reported by Lai-Xi Wang and coworkers, University of Maryland, US. Their cover image shows the interaction between human antibody 2G12 and a synthetic oligomannose cluster.