Eight novel organic sulfur compounds featuring an unprecedented
structure among natural organosulfur molecules are reported. The identified
compounds, named dirchromones (1−8), were isolated from a dichloromethane extract
of the roots, bark, and wood of Dirca palustris, an endemic shrub of eastern North
America. Their identification was based on thorough NMR, IR, and HRMS
spectroscopic data interpretation. These compounds showed cytotoxic and mild
Gram-positive antibacterial activities in vitro, while being inactive against Gram-negative
Escherichia coli and the yeast Candida albicans. This is the first report of sulfur-containing
compounds from a species of the Thymelaeaceae.