722 J. Am. Chem. Soc., Vol. 106, No. 3, 1984 establish the stereochemistry of C-3a and C- 8b relative to C-Sa. We assumed from the outset that control of these centers would be crucial to the success of the plan. In practice, however, the center at C-8b proved to be of little strategic importance since the natural product possesses the thermodynamically most stable configuration at this center.
