Editorial [Hot Topic: Natural Product Chemistry issue (Guest Editor: K. Hostettmann)]

The 2007 Natural Product Chemistry issue of Current Organic Chemistry provides four chapters covering various bioactivities of natural products. The first contribution, by Adams and Bauer, involves plant metabolites which inhibit leukotriene biosynthesis. Leukotrienes, biosynthesized from fatty acids, play important roles in inflammation, bronchoconstriction, chemotaxis and blood vessel permeability. Inhibitors of leukotrienes are therefore of potential importance in several disease states. Although reviews of leukotriene biosynthesis inhibitors have been published, it is important to update advances made in the field and to discover new and more selective inhibitors. Plant metabolites provide an excellent source of such compounds. Bryophytes are also a source of novel metabolites. They have supplied many interesting isoprenoids and aromatic compounds. In China, there are over 3400 different species of bryophyte and Xie and Lou summarize data obtained in their laboratory on the constituents and bioactivities of a number of species, collected from all over China. Their focus is on the antifungal activities of the isolated compounds. This is because the explosion of opportunistic infections and the development of resistance to current antifungal drugs in humans urgently require new antifungal therapeuticals. Another area desperately in need of new therapeuticals is the domain of the so-called “neglected” diseases. Far too little funding and research goes into the tropical parasitic diseases leishmaniasis, sleeping sickness, Chagas disease and malaria. In the latter, though, there has been some improvement in the situation with the introduction of artemisinin. Artemisinin, a sesquiterpene lactone from the Chinese plant Artemisia annua (Asteraceae), is a very effective antimalarial compound which is important for the treatment of patients affected by resistant strains of the parasite. However, in order to be one step ahead of the resistance phenomenon, new drugs need to be in the pipeline. Ioset describes the most promising compounds for malaria and the other diseases that have recently been isolated from living organisms. A critical update is also provided on their current development status. The final contribution involves a sub-group of the saponins, the substance class which are glycosides of triterpenes or steroids. In this article, Foubert, Theunis, Apers, Vlietinck and Pieters treat the13,28-epoxy-oleanane saponins, almost all of which are found in species of the Primulaceae or Myrsinaceae plant families. They possess antiviral, haemolytic, molluscicidal and anti-angiogenic activities. In addition, there is a link to the article by Ioset because saponins from Maesa balansae (Myrsinaceae) have antileishmanial properties. I would like to express my sincere thanks to all contributors in this volume for the excellent reviews of natural product research that they have produced.