Synthetic studies on pseudoguainolides. I. Preparation of a key intermediate, 1.BETA.-tert-butoxyl-2,3,3a.ALPHA.,4,5,8a-hexahydro-4.ALPHA., 8a.BETA.-dimethyl-6(1H)-azulenone, for helenanolides.
Synthetic studies on pseudoguainolides. I. Preparation of a key intermediate, 1.BETA.-tert-butoxyl-2,3,3a.ALPHA.,4,5,8a-hexahydro-4.ALPHA., 8a.BETA.-dimethyl-6(1H)-azulenone, for helenanolides.