Synthesis of (+)-Frondosin B

Significance

(+)-Frondosin B was isolated from the marine sponge Dysidea frondosa in 1997. It has a broad spectrum of biological activity including anti-inflammatory properties, potential for use in anticancer and HIV therapy, and to date there have been three reported enantioselective total syntheses. There has been some discrepancy about the absolute configuration of the benzylic stereocenter C8, when the Trauner group’s synthesis led to the opposite stereochemical assignment to that proposed by Danishefsky.