Four novel alkaloids, bispyrrocidine (5), the epoxy derivative of pyrrocidine B (6), 19-O-methyl-pyrrrocidine B (7) and 19-O-ethyl-pyrrrocidine B (8) were isolated from the endophytic fungus Neonectria ramulariae Wollenw KS-246. Their structures were elucidated using 1D- and 2D-NMR spectroscopy. Compound 6 exhibited cytotoxicity against HL60 cells (IC 50 4.6 μM), whereas 5 showed specific inhibitory activity against prolyl oligopeptidase (IC 50 2.6 μM) in a non-competitive manner.
- Neonectria ramulariae
- Prolyl oligopeptidase inhibitor
ASJC Scopus subject areas
- Agronomy and Crop Science
- Plant Science