Chemical Constituents from the Fermented Mycelia of the Medicinal Fungus Xylaria nigripes

Nineteen compounds mainly including pyrrole-containing alkaloids and phytosterols were isolated from the EtOH extract of the fermented mycelia of Xylaria nigripes, a precious medicinal fungus known as Wuling Shen in Chinese. On the basis of spectroscopic methods, the structures of the new naturally occurring compounds were determined to be (4S)-3,4-dihydro-4-(4-hydroxybenzyl)-3-oxo-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (1), methyl (2S)-2-[2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl]-3-(4-hydroxyphenyl)propanoate (2), and 3-{4-[(2R)-(2,3-dihydroxy-3-methylbutoxy]phenyl}-7-hydroxy-4H-chromen-4-one (3), respectively. The absolute configurations of 1 and 2 were deduced by the observed Cotton effects in their circular dichroism (CD) spectra, whereas that of the 1,2-diol moiety in 3 was determined using the Snatzke's method. Their biological activities such as neuroprotective, anti-neuroinflammatory, and cytotoxic properties were also reported.