Gutingimycin: A Highly Complex Metabolite from a Marine Streptomycete

An intriguing catch: Gutingimycin (1) from the marine streptomycete isolate B8652 is a conjugate of guanine and trioxacarcin A, as extensive NMR measurements and a crystal structure analysis show. The natural product is formed most likely by the selective attack of trioxacarcin A on the bacterial DNA, which results in strand breakage and may explain the high cytotoxicity of the latter.