new viriditoxin derivative (1), together with viriditoxin (2) and two
previously reported viriditoxin congeners (3 and 4).18,19 Viriditoxin
(2) was first isolated from Aspergillus viridinutans as a mycotoxin,
whereas it was later also obtained from Aspergillus brevipes, Aspergillus
fumigatus, Paecilomyces variotii and Spicaria divaricata.18–20 Details on
the isolation and structure elucidation of 1, its biological activity and
the plausible biogenesis of the isolated compounds are reported
herein.
RESULTS AND