Total synthesis of tricyclic-PGDM methyl ester (3). TBS = tert-butyldimethylsilyl, NIS = N-iodosuccinimide, DCM = dichloromethane, TBAF = tetrabutylammonium fluoride, DMAP = 4-(dimethylamino)pyridine, DIPEA = N,N-diisopropylethylamine, AIBN = 2,2’-azobis(2-methylpropionitrile), THF = tetrahydrofuran, DCE = 1,2-dichloroethane, DDQ = 2,3-dichloro-5,6-dicyano-p-benzoquinone, KHMDS = potassium bis(trimethylsilyl)amide.