Ardeemins and Cytochalasins from Aspergillus terreus Residing in Artemisia annua

Abstract

Three new alkaloids, 15b-dehydro-5-N-acetylardeemin (3), 10-phenyl-[12]-cytochalasins Z16 (6) and Z17 (7), were characterized from the liquid culture of the endophytic fungus Aspergillus terreus IFB-E030 along with six known derivatives, 5-N-acetylardeemin (1), 15b-β-hydroxyl-5-N-acetylardeemin (2), cytochalasin E (4), rosellichalasin (5), cytochalasins Z11 (8), and Z13 (9). The structures of the new metabolites were established mainly by a combination of their 1D- and 2D‐NMR spectra, single crystal X‐ray diffraction, and the modified Mosher reaction. Biological assays indicated that cytochalasin Z17 (7) had moderate cytotoxicity against human nasopharyngeal epidermoid tumor KB cell line with an IC₅₀ value of 26.2 µM.

Key words

structure determination - natural products - Aspergillus terreus - ardeemin - cytochalasin

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