Shikometabolins A, B, C and D, novel dimeric naphthoquinone metabolites obtained from shikonin by human intestinal bacteria
摘要:
Shikometabolins A (2), B (3), C (4) and D (5), four novel naphthoquinone dimers, have been isolated after anaerobic incubation of shikonin (1) with Bacteroides fragillis subsp. thetaotus, and their structures have been determined by means of 2-D NMR spectroscopy including INADEQUATE experiments.