Peniandranoids A-E: Meroterpenoids with Antiviral and Immunosuppressive Activity from a Penicillium sp.

Peniandranoids A-E (1-5), five new meroterpenoids, together with three known analogues (6-8), were isolated from the fermentation of a soil-derived fungus, Penicillium sp.sb62. Their structures including absolute configurations were determined by extensive spectroscopic analysis, and the absolute configurations of compounds 1 and 5 were further elucidated by single-crystal X-ray diffraction. Peniandranoids A-E belong to a rare class of andrastin-type meroterpenoids incorporating an extra polyketide unit (a C10 polyketide unit for 1 and 2, a C9 polyketide unit for 3 and 4, and a furancarboxylic acid unit for 5). Compounds 1 and 6 exhibited favorable inhibitory activities against influenza virus A (H1N1) with EC50 values of 19 and 14 mu g/mL, respectively. Compounds 3-8 exhibited potent immunosuppressive activities against concanavalin A-induced T cell proliferation with EC50 values ranging from 4.3 to 27 mu M and lipopolysaccharide-induced B cell proliferation with EC50 values ranging from 7.5 to 23 mu M, respectively.

Automated summary

Five new meroterpenoids, Peniandranoids A-E (1-5), along with three known analogues (6-8), were isolated from the fermentation of a soil-derived fungus, Penicillium sp.sb62. The structures and absolute configurations of these compounds were determined by extensive spectroscopic analysis, with the absolute configurations of compounds 1 and 5 further confirmed by single-crystal X-ray diffraction. Peniandranoids A-E are a rare class of andrastin-type meroterpenoids that incorporate an extra polyketide unit, with compound 1 and 2 containing a C10 polyketide unit, compound 3 and 4 containing a C9 polyketide unit, and compound 5 containing a furancarboxylic acid unit. Compound 1 and 6 showed favorable inhibitory activities against influenza virus A (H1N1) with EC50 values of 19 and 14 μg/mL, respectively. Compounds 3-8 exhibited potent immunosuppressive activities against concanavalin A-induced T cell proliferation with EC50 values ranging from 4.3 to 27 μM and lipopolysaccharide-induced B cell proliferation with EC50 values ranging from 7.5 to 23 μM, respectively.