Streptoverticillium ehimense Carbazomycins

In 1988, Nakamura et al. reported the isolation of carbazomycins G (269) and H (270) from the culture broth of Streptoverticillium ehimense. These alkaloids have a structurally unique carbazole-l,4-quinol framework and were obtained from Nature in racemic form. Carbazomycin G showed moderate antifungal activity against... 

Carbazomycin G and H have been isolated from Streptoverticillium ehimense [38]. In nature carbazomycin G occurs as a racemic mixture and the same is assumed for carbazomycin H. Garbazomycin G was reported to show antifungal activity. The two compounds share a unique structure, namely the carbazole-l,4-quinol moiety. Starting from the appropriate iron complex salt, iron-mediated arylamine cydization provides a simple route to both alkaloids (Scheme 15.10) [39]. 

Carbazomycins. The carbazole alkaloids C. A-H are isolated from cultures of Streptoverticillium ehimense (syn. S. abikoense), e.g. C. A C,6H,7N02, Mr 255.31, yellow needles, mp. 143-146 °C. C. are antibiotics and interesting synthetic targets. 

The hyellazoles (3) isolated from the blue green alga Hyella caespltosa, and the carbazomycins (4) produced by the actinomycete Streptoverticillium ehimense, show a substituent pattern different from the Rutaceae carbazole alkaloids They all share the common features of carbon substituents in the 1 and 2-positions, and an oxygen functionality in the 3-position. Antibiotic activity is reported for carbazomycin B (4b).32... 

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