ABSTRACT
Coumarins, derivatives of cinnamic acid, are secondary metabolites that are widely distributed in the vegetal kingdom, both in the free form and as glycosides. More than 1300 coumarins have been isolated and reported from natural sources, particularly belonging to the Rutaceae, Apiaceae, Fabaceae, and Asteraceae families (Thuong et al. 2010). Coumarins show multiple bioactive properties. such as antioxidant, chemotherapeutic, antimicrobial, and anticoagulant activities, among others (Yu et al. 2005). The basic structure of coumarins, also known as benzo-2-pyrones, consists of the union of a benzene ring and a pyrane ring. Depending on the substituents, coumarins are structurally diverse, as they can yield hydroxylated, alkylated, and alkoxylated derivatives from the parent compound. They can even contain
13.1 Introduction .................................................................................................. 389 13.2 Natural Occurrence of Coumarins in Citrus ................................................390
