20-nor-Isopimarane and isopimarane diterpenoids produced by Aspergillus sp. WT03

Abstract

Five new uncommon 20-nor-isopimarane diterpenoids, aspewentins N-R (1-5), and three related known congeners (6-8), along with an isopimarane diterpenoid, sphaeropsidin C (9), were isolated from a Coptis chinensis Franch. rhizosphere...

The incredible story of ophiobolin A and sphaeropsidin A: two fungal terpenes from wilt-inducing phytotoxins to promising anticancer compounds

“…Furthermore, a decrease in the number of cancer cells, changes in cell morphology, rupture of cells and cell debris were observed in comparison to the control. 178 Six isopimarane-type diterpenoids named botrysphins A-F (163-168, Fig. 14), were isolated from culture of Botrysphaeria laricina, together with three triketides named botrysphones A-C, sphaeropsidone and chlorosphaeropsidone, respectively.…”

“…The tricyclic pimarane system is an important feature to impart activity given that its disruption observed in derivative 180 strongly reduced the activity. The antimycotic activity of sphaeropsidins A-F (2,(135)(136)(137)(138)(139) and their derivatives (173)(174)(175)(176)(177)(178)(179)(180), respectively, was assayed against eight fungal species including S. cardinale, S. cupressi, and S. unicorne, which are causal agents of cypress canker disease, and ve other plant pathogenic fungi, namely, Botrytis cinerea, Fusarium oxysporum, Penicillium expansum, Phomopsis amygdali and Verticillium dahlia. Among the fungi tested, SphA showed the strongest antifungal activity against P. amygdali, while it was reduced against F. oxysporum and V. dahlia, which appeared to be less sensitive to the toxin.…”

“…To achieved this goal, 14 derivatives of sphaeropsidins A-C were prepared by chemical transformation. In addition to the above-cited derivatives (173)(174)(175)(176)(177)(178)(179)(180), SphA was converted by catalytic hydrogenation followed by the usual acetylation into the corresponding 7-O-acetyl-7,O,15,16-terahydro derivative (181, Fig. 15), while its milder hydrogenation yielded the 15,16-dihydroderivative (182, Fig.…”

“…Furthermore, a decrease in the number of cancer cells, changes in cell morphology, rupture of cells and cell debris were observed in comparison to the control. 178…”