Cinerols, Nitrogenous Meroterpenoids from the Marine Sponge Dysidea cinerea

Eleven new nitrogenous meroterpenoids, cinerols A–K ( 1 – 11 ), were isolated from the marine sponge Dysidea cinerea collected in the South China Sea, and their structures were determined by detailed spectroscopic analysis. Cinerols A ( 1 ) and B ( 2 ) feature a rare 5 H -pyrrolo[1,2a]benzimidazole moiety, while cinerols C–G ( 3 – 7 ) are examples of rare meroterpene benzoxazoles. The cinerols are noncytotoxic to human melanoma A375 cells at the concentration of 32 μM; however, selected cinerols exhibit moderate inhibitory activity against one or more of protein-tyrosine phosphatase 1B, ATP-citrate lyase, and SH2 domain-containing phosphatase-1 with IC 50 values of 2.8–27 μM.