The bowl-shaped tricyclo[6.3.1.0^4,12]dodecane moiety is the core feature of cephalotane-type diterpenoids. As part of our efforts directed towards a total synthesis of mannolide B, the bowl-shaped tricyclo[6.3.1.0^4,12]dodecane skeleton, a common intermediate of cephalotane-type diterpenoids bearing up to five contiguous stereocenters including two quaternary carbon centers had been constructed. The synthetic strategy was enabled by an efficient application of oxidative dearomatization/intramolecular Diels-Alder reaction to access highly functionalized building block with the tricyclo[5.2.2.0^2,6]undecane unit from commercially available materials. The key feature was firstly used the cyclic olefins with secondary alcohol as dienophile for the intramolecular inverse electron demand Diels-Alder reaction. Further synthetic studies led to construct ring D by a regioselective Aldol reaction.

碗形的三环[6.3.1.0 ^4,12 ]十二烷部分是头烷类二萜的核心特征。作为致力于全合成甘露糖苷B的努力的一部分，碗形三环[6.3.1.0 ^4,12 ]十二烷骨架是头孢烷型二萜类化合物的常见中间体，带有多达五个连续的立体中心，包括两个季碳中心。被建造。通过有效地应用氧化脱芳香化/分子内Diels-Alder反应来访问具有三环[5.2.2.0 ^2,6]的高度官能化的结构单元，从而实现了合成策略由市售材料制成的十一烷单元。关键特征是首先将环烯烃与仲醇作为亲二烯体用于分子内逆电子需求Diels-Alder反应。进一步的合成研究通过区域选择性Aldol反应导致构建环D。