Four prenylated indole alkaloids (1-4) were targeted isolated from the mangrove rhizosphere soil-derived fungus Penicillium janthinellum HK1-6 by using molecular networking strategies. Among them, the planar structure and relative configuration of notoamide X (1) were elucidated by detailed analysis of the spectroscopic data especially the NOESY spectrum for the first time and its absolute configuration was determined by ECD spectrum. Furthermore, curated molecular networks of MS/MS data were generated with GNPS which allowed highlighting six prenylated indole alkaloids (5, 6, 8, 9, 11, 12) that had not previously been identified in this fungus and two (7, 10) that had never been observed in any fungus. The MS/MS fragmentation pathway of these prenylated indole alkaloids was summarized.
Keywords: Marine-derived fungus; Penicillium janthinellum; molecular networking; notoamide; paraherquamide; prenylated indole alkaloid.