ARS | Publication request: Isolation, structure elucidation, and biomimetic total synthesis of versicolamide B and the isolation of antipodal (-)-stephacidin A and (+)-notoamide B from Aspergillus versicolor

Submitted to: Angewandte Chemie
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 22, 2008
Publication Date: April 3, 2008
Citation: Greshock, T.J., Grubbs, A.W., Jiao, P., Wicklow, D.T., Gloer, J.B., Williams, R.M. 2008. Isolation, structure elucidation, and biomimetic total synthesis of versicolamide B and the isolation of antipodal (-)-stephacidin A and (+)-notoamide B from Aspergillus versicolor. Angewandte Chemie. 47(19):3573-3577.

Interpretive Summary: Fungi that parasitize and kill other fungi offer a potential source of novel antifungal agents useful to agriculture and medicine. The fungus Aspergillus versicolor NRRL 35600, encountered as a colonist of a wood decay fungus in Hawaii, was examined for its ability to produce antifungal agents and other bioactive metabolites. Versicolamide B is reported as new metabolite belonging to a family of alkaloids known for its myriad of biological activities. The total synthesis of versicolamide B is reported and the implications of its rare stereochemistry are discussed.

Technical Abstract: A new prenylated indole alkaloid, versicolamide B, was isolated from cultures of Aspergillus versicolor NRRL 35600. The structure was assigned by 2D NMR data, and confirmed by a biomimetic total synthesis. Versicolamide B is the first member of the paraherquamide-stephacidin family of alkaloids found to possess the anti-relative stereochemistry at C19. Ent-Stephacidin A and ent-notoamide B were also isolated for the first time from these cultures.