Succinic acid allyl ester (2S,3R,6S,8R,9S)-2-((1E,3E)-4-allyloxycarbonyl-3-methyl-buta-1,3-dienyl)-3-butyl-8-((E)-4-hydroxy-3-methyl-but-2-enyl)-9-methyl-1,7-dioxa-spiro[5.5]undec-3-yl ester