Nakijiquinones G–I, new sesquiterpenoid quinones from marine sponge Original Research Article

Three new sesquiterpenoid quinones, nakijiquinones G–I (1–3), containing a different amino group derived from amino acids have been isolated from Okinawan marine sponges of the family Spongiidae, and the structures and relative stereochemistry of 1–3 were elucidated on the basis of the spectral data. Nakijiquinones G–I (1–3) showed modest cytotoxicity and inhibitory activity against HER2 kinase, while nakijiquinone H (2) exhibited antimicrobial activity.