(1R,5S,8R,9S,11R)-9-(bromomethyl)-4,11-bis(hydroxymethyl)-5,9-dimethyl-10-oxotricyclo<6.2.1.01.5>undec-3,6-diene

[(1R,2S,6R)-6-(1,1-dimethylethyl)dimethylsilyloxy-2-(4-methoxybenzyloxy)-3-methylcyclohex-3-en-1-yl]carbaldehyde