Acylphloroglucinols as kinase inhibitors from Sargassum nigrifoloides

AbstractThree new acylphloroglucinols (1–3) and four known biosynthetically related analogs (4–7) were isolated from the ethanol extract of a brown alga Sargassum nigrifoloides. Structures for 1–7 were characterized via detailed spectroscopic analyses especially 2D NMR data. Screening of these compounds in Alzheimer’s diseases-related bioassays revealed moderate inhibitory activities against two therapeutically important kinases, CDK5 and GSK3β. A preliminary structure–activity relationship was also discussed.