h key step in the lirst synthesis of racemic altersolanol A ( l a ) is rlic regiosclcctivc Diels-Alder reaction of 5-acetoxy-7-methoxy-1.4-naphtlioyuinone (12) with 2-methyl-l-(trimethylsiloxy)-1.3-hutadicnc (13) 10 afTord ihc adduct 14. Thc structure of 14 has hccn confirmed by X-ray mcasurcmcnts. The hydroxy groups of ring A arc introducod hy cpoxidation of 14 to 20, rearrangement t o the allylic ;ilcohol 26, epoxidation to 31, and opening of the iwiranc to rtrc~-altcrsolanol A (1 a). Similar products were obtained stwting from juglonc (15). Many ofthc intermediate cpoxidcs and also compounds 42 -44 show remarkable cytotoxicity in all culturcs hut all conipounds were too toxic to be useful as anticancer apcnts.Altersolanol A (1 a) (identical with stemphylin and altersolanol B (lb), dactylariol(2) and bostrycin (4a) are closely related tetrahydroanthraquinone antibiotics that occur in various species of f~n g i~-~) .Recently two related pigments, austrocortilutein (3) and austrocortirubin (4 b) from the subgenus Derrrzocybe of Cortinarius, were also isolated6). The names of the antibiotics are related to their origins in Alternaria solani7>'), Dactylaria lutes'), and Bostrychonema alpstre") ( naphthazarin to related tri-and tetracyclic quinone antibiotic~'~'.We now describe the first total synthesis of racemic la, in which a similar strategy for the construction of the tetra-

The cycloaddition reaction of the diene (II) with the naphthoquinone (I) gives the adduct (III) (space group P21/n; Z=4) which is transformed to the title compound (VII) as shown.