Stoechospermol, synthesis

Photo-cycloaddition in the enone (16) yields the adduct (17) which was used as a key step in a new synthesis of stoechospermol. Adduct (18) is formed in high yield on irreuliation of enone (19) in a variety of solvents. ... 

Miesch, M., Cotte, A., and Franck-Neumann, M. (1994) Total synthesis of ( ) stoechospermol. Tetrahedron Lett., 35, 7031-7032. 

Tanaka, M., Tomioka, K., and Koga, K. (1994) Enantioselective total synthesis of (+)-stoechospermol via stereoselective intramolecular (2+2) photocycloaddition of the chiral butenolide. Tetrahedron, 50, 12829-12842. 

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