Journal or Book Title
The Journal of Organic Chemistry
A 10-step route to the BCDE ring system of quasimarin (1) is described. Key features of the route include the regioselective protection of diketone 7 by use of intramolecular ketal formation, a two-step lactone to ether reduction, and a regioselective lactonization. The tetracyclic system 15 is produced in 29% overall yield.
American Chemical Society
Kraus, George A.; Taschner, Michael; and Shimagaki, Masayuki, "An approach to the BCDE ring of quasimarin" (1982). Chemistry Publications. 703.