Naphthoquinones from Verbenaceae

Naphthoquinones isolated from the wood of trees of the families Bignoniaceae and Verbenaceae have been subjected to an interdisciplinary study since the seventies, when Dr. Gilbert, at the Federal University of Rio de Janeiro, launched a program on the chemistry of natural products active against endemic diseases. Recently, De Moura etal. [209] have described the synthesis of five naphthoimidazoles derived from this program and their... 

Anthraquinones in which only one ring is substituted are particularly common in the Bignoniaceae, Rubiaceae, and Verbenaceae, but do not appear to occur in fungi, the Poly-gonaceae, Rhamnaceae, Fabaceae, Caesalpinioideae, or the Liliaceae (A/oe). These compounds are derived from a pathway similar to that previously discussed for naphthoquinones, but with subsequent addition of mevalonate-derived units (Fig. 6.8). 

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