摘要：

Coumarins comprise a large group of natural compounds isolated from many plant or microbial sources, and novel derivatives are still being reported each year.1,2 Their classification is based on the 2H-benzopyrane-2-one core structure, which almost always bears an oxygen in position 7 as in umbelliferone (Fig. 1). Despite the wide taxonomic distribution of these metabolites, the mechanism of coumarin biosynthesis has been resolved only partially, and few in vitro studies had addressed this problem till the early eighties.3–4 The situation changed markedly, however, when the activation of coumarin biosynthesis in response to fungal challenge or other stress conditions was reported from various plants and plant cell cultures.5–21 Induced cell cultures of the Apiaceae, in particular, paved the road to detailed molecular and regulatory studies, and significant progress has been accomplished recently. Furthermore, it has long been known that some coumarins show remarkable bioactivities, e.g. the anticoagulant effect of 4-hydroxycoumarins or the antiproliferative and phototoxic action of linear furanocoumarins as well as the inhibitory action on 5-lipoxygenases.22–24 More recently, new and surprisingly diverse activities have been ascribed to other coumarins, some of which have received public attention and may serve as lead structures in drug development. A few such examples will be considered before briefly reviewing some recent developments in the research of biosynthesis.

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