Denigrins and Dactylpyrroles, Arylpyrrole Alkaloids from a sp. Marine Sponge.

Seven new arylpyrrole alkaloids (-), along with four known compounds, were isolated from an extract of a sp. nov. marine sponge, and their structures were elucidated by interpretation of NMR and MS spectroscopic data. Denigrins D-G (-) have highly substituted pyrrole or pyrrolone rings in their core structures, while dactylpyrroles A-C (-) have tricyclic phenanthrene cores. Due to the proton-deficient nature of these scaffolds, key heteronuclear correlations from H-N HMBC and LR-HSQMBC NMR experiments were used in the structure assignment of denigrin D (). Dictyodendrin F (), a previously described co-metabolite, inhibited transcription driven by the oncogenic PAX3-FOXO1 fusion gene with an IC value of 13 μM.