Daldispones A and B, two new cyclopentenones from Daldinia sp. CPCC 400770

Eleuthemarins A and B, two new isocoumarin derivatives from the Arctic fungus Eleutheromyces sp. CPCC 401592

Two new isocoumarin derivatives, eleuthemarins A (1) and B (2), were isolated from the Arctic fungus Eleutheromyces sp. CPCC 401592. Their structures and absolute configurations were elucidated through spectroscopic methods, quantum chemical calculations of NMR shifts, and calculated electronic circular dichroism. This is the first report for the chemical investigation of the genus Eleutheromyces. Compounds 1 and 2 showed selective cytotoxic activities against H460, A549, and HCT116 cancer cell lines with IC50 values in the range of 24.1-57.3 μM, respectively. Compound 1 displayed weak antibacterial activities.

Two new cyclopentenone metabolites from Streptomyces sp. HU119

Two previously undescribed cyclopentenone metabolites, (S)-2-(3-acetylamino-2-methyl)propyl-3-butyl-2-cyclopenten-1-one (1) and (S)-2-(3-acetylamino-2-ethyl)propyl-3-butyl-2-cyclopenten-1-one (2), were isolated from the fermentation broth of the strain Streptomyces sp. HU119. The structures of 1 and 2 were determined by the comprehensive spectroscopic analysis, including 1 D, 2 D NMR, MS spectral analysis and the comparison with data from the literature. The absolute configurations were elucidated by experimental and calculated optical rotations (OR). Compounds 1 and 2 displayed weak cytotoxic activity.

New phenol and chromone derivatives from the endolichenic fungus Daldinia species and their antiviral activities

Three new phenolic metabolites, daldispols A–C (1–3), two new chromone derivatives, (5R,7R)-5,7-dihydroxy-2-methyl-5,6,7,8-tetrahydro-4H-chromen-4-one (9) and (5R,7R)-5,7-dihydroxy-2-propyl-5,6,7,8-tetrahydro-4H-chromen-4-one (10), together with five known phenolic compounds (4–8) and two known chromone compounds (11 and 12) were isolated from the endolichenic fungus Daldinia sp. CPCC 400770. Their structures were elucidated on the basis of spectroscopic methods, electronic circular dichroism (ECD), and comparison with reported data. Compounds 1, 3, 4, 9, and 11 exhibited significant anti-influenza A virus (IAV) activities with IC₅₀ values of 12.7, 6.4, 12.5, 16.1, and 9.0 μM, respectively, and compound 8 displayed significant anti-ZIKV activity with inhibitory ratio of 42.7% at 10 μM. The results demonstrated that the fungus Daldinia sp. CPCC 400770 might be a rich source for discovering anti-IAV secondary metabolites as potential novel leading compounds.

Eight phenols including three new ones (1–3) and four chromones including two new ones (9 and 10) were isolated from endolichenic fungus Daldinia sp. CPCC 400770, and some of them showed significant antiviral activities.