Cytotoxic 5-hydroxyindole alkaloids from the marine sponge Scalarispongia sp.

Abstract

Three new 5-hydroxyindole alkaloids along with seven known analogs were isolated from a Dokdo marine sponge Scalarispongia sp.. The elucidation of the structures of the new compounds by spectroscopic analyses indicated that these compounds were an indole glyoxylate, a mono-indole analog of hyrtinadine A, and a symmetrical bis-indole with pyridine linker. The comparison of IC50 values for obtained compounds against a human leukemia cell line revealed that the bis-indole structure is an essential for the cytotoxicity.nds were an indole glyoxylate, a mono-indole analog of hyrtinadine A, and a symmetrical bis-indole with pyridine linker. The comparison of IC50 values for obtained compounds against a human leukemia cell line revealed that the bis-indole structure is an essential for the cytotoxicity.