Metabolites
1
and
2
, isolated
from cultures
of the basidiomycete
Resupinatus
sp. BCC84615, collected
in a tropical forest in northeastern Thailand, showed weak antibiotic
activity against
Bacillus subtilis
and
Staphylococcus
aureus
and cytotoxicity against cancer cell lines. Their
planar structures were elucidated by high-resolution electrospray
ionization mass spectrometry and NMR spectroscopy as clavilactone
J, known from the basidiomycete
Ampulloclitocybe clavipes
, and its new 1,4-benzoquinone derivative. A detailed analysis of
the ROESY correlations in
1
confirmed the recent revision
of the relative configuration of clavilactone J. However, specific
rotation and Cotton effects observed by electronic circular dichroism
were contrary to those of the clavilactones; thus, we assigned a rare
antipodal absolute configuration.