Antibiotic Properties of Thiarubrine A, a Naturally Occurring Dithiacyclohexadiene Polyine

Thiarubrine A, a dithiacyclohexadiene polyine from the roots of CHAENACTIS DOUGLASII, exhibits strong antifungal activity towards CANDIDA ALBICANS and ASPERGILLUS FUMIGATUS at concentrations comparable to those of amphotericin B. It also exhibits cytotoxic activity towards ESCHERICHIA COLI and BACILLUS SUBTILIS and the nematode COENORHABDITIS ELEGANS. A thiophene derived from thiarubrine A was shown to be phototoxic, requiring UV-A light for biological activity. The effects of thiarubrine A, thiophene A and α-terthienyl on the above organisms, as well as on CHO cells, were compared.