Naphthoquinones, Higher Quinones, and Related Compounds

Isomarinone (1679), an isomer of the previously known marinone (7), was isolated from the same tropical sediment bacterium (1638). Another marine-derived bacterium related to the genus Streptomyces has yielded the novel azamerone (1680) (1639). The British Columbian medicinal plant Moneses uniflora contains the antibiotic 8-chlorochimaphilin (1681), which is more active than chimaphilin (1640). Sesame roots (Sesamum indicum) have yielded the red chlorinated naphthoquinone chlorosesamone (1682) (1641). Cultures of Streptomyces strain LL-A9227 produce chloroquinocin (1683), which has some antibacterial activity against Gram-positive bacteria (1642). The two xestoquinones 1684 and 1685 were characterized from the Philippino sponge Xestospongia sp., and display topoisomerase II activity (1643). 

A synthesis of the chlorinated angucycline antibiotic BE-23254 (1686), which was isolated from Streptomyces sp. A 23254, has confirmed the structure of this benz[a anthraquinone derivative (1644,1939,1940). Two detailed examinations of the rare Australian soil actinomycete Kibdelosporangium sp. uncovered a series of 

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