Capraria biflora

Infections. Copaifera langsdotffii Desf. and other spp (Leguminosae, Caesalpinaceae) Altemanthera brasiliana (L.) Kuntze and other sp. (Amaranthaceae) Lippia gracillis L microphylla Cham., L aff. alnifolia Mart, et Schauer, L. sidoides Cham. (Verbenaceae) Capraria biflora L. (Scrophulariaceae) trunk oil aerial part leaves leaves, flowers... 

Structurally related is biflorin (351), isolated from Capraria biflora, and the first naphtho[l,8-hc]pyranquinone found in nature. It has antibiotic properties. Its structure was determined by Prelog and co-workers (58HCA1386 63HCA409, 63HCA415) and it was synthesized by an intramolecular Diels-Alder addition between a benzyne and furan (86AJC647). 

Only a few compounds have the carbon skeleton of the geranylmenthane cation (471), mostly isolated from genus Helichrysum - e.g., peroxide 474 from roots of H. acutatum (40). Compounds of the prenylgermacrane type (472) have not, so far, been isolated from higher plants however, the bluish-red antibiotic biflorin (475), occurring in the roots of Capraria biflora (105), is an example of a type arising from further cyclization of 472 (cf. cadalanes in Sect. 8.1.3.3.2, Ses-quiterpenoids). 

---