0000000000305545
AUTHOR
Jungho Lee
Azacoccones F-H, new flavipin-derived alkaloids from an endophytic fungus Epicoccum nigrum MK214079.
Abstract Three new flavipin-derived alkaloids, azacoccones F-H (1–3), along with six known compounds (4–9) were isolated from the endophytic fungus Epicoccum nigrum MK214079 associated with leaves of Salix sp. The structures of the new compounds were established by analysis of their 1D/2D nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectroscopy (HRESIMS) data. The absolute configuration of azacoccones F-H (1–3) was determined by comparison of experimental electronic circular dichroism (ECD) data with reported ones and biogenetic considerations. Epicocconigrone A (4), epipyrone A (5), and epicoccolide B (6) exhibited moderate antibacterial activity again…
Cladosins L-O, new hybrid polyketides from the endophytic fungus Cladosporium sphaerospermum WBS017
Abstract The endophytic fungus Cladosporium sphaerospermum WBS017 was obtained from healthy bulbs of Fritillaria unibracteata var. wabuensis. Fermentation of C. sphaerospermum on solid rice medium yielded three new hybrid polyketides, cladosins L−N (1–3), and a known derivative cladodionen (4). Further cultivation of this fungus on white bean medium afforded an additional new hybrid polyketide, cladosin O (5) along with three known analogues (6–8). The structures of the new compounds were elucidated using a combination of NMR and HRESIMS data. The absolute configurations of compounds 2 and 3 were determined by Mosher’s method and TDDFT-ECD calculations. All isolated compounds were evaluated…
Dithiodiketopiperazine derivatives from endophytic fungi Trichoderma harzianum and Epicoccum nigrum
A new epidithiodiketopiperazine (ETP), pretrichodermamide G (1), along with three known (epi)dithiodiketopiparazines (2-4) were isolated from cultures of Trichoderma harzianum and Epicoccum nigrum, endophytic fungi associated with medicinal plants Zingiber officinale and Salix sp., respectively. The structure of the new compound (1) was established on the basis of spectroscopic data, including 1D/2D NMR and HRESIMS. The isolated compounds were investigated for their antifungal, antibacterial and cytotoxic potential against a panel of microorganisms and cell lines. Pretrichodermamide A (2) displayed antimicrobial activity towards the plant pathogenic fungus Ustilago maydis and the human path…