Total Synthesis Construction of Key Intermediates 86 and 87 Meo me Me OTMS H。MeH E FG AB C OTBS 87 EtS EtS OTPS H 86Total Synthesis Construction of Key Intermediates 86 and 87 O O O O O O O Me H H H H H H Me H Me H H Me Me Me A OTMS PPh3 87 B C D E F G O O O H H OTBS EtS H Me I EtS H H O J K OTPS 86