1-NAPHTHALENECARBOXYLIC ACID, 6-[[(1,1-DIMETHYLETHYL)DIMETHYLSILYL]OXY]-5-[[[(1,1-DIMETHYLETHYL)DIMETHYLSILYL]OXY]METHYL]-2-ETHENYLDECAHYDRO-1,5,8A-TRIMETHYL-, METHYL ESTER, (1S,2R,4AR,5R,6S,8AS)-