Icetexane type diterpene dimer compound as well as preparation method and application thereof

The invention discloses an Icetexane type diterpene dimer compound as well as a preparation method and an application thereof. The Icetexane type diterpene dimer compound is separated from a perovskia plant, is the first diterpene dimer with an intramolecular hemiketal structure formed by C-11 carbonyl and C-10 hydroxyl of a C-ring so far, is named biperovskatone, and has the molecular formula of C40H56O6 as well as the structure shown in the specification. According to the Icetexane type diterpene dimer compound, the whole dried perovskia plant is taken as the raw material, is extracted by an extract and an organic solvent and subjected to silica column chromatography, reversed-phase column chromatography and HPLC (high pressure liquid chromatography) separation to obtain a product. The compound has obvious inhibitory activity on an HBsAg (hepatitis B surface antigen) and an e antigen HBeAg secreted by an HepG2.2.15 cell and can reduce HBV (hepatitis B virus) DNA (deoxyribonucleic acid) in the cell substantially. The compound is diterpene dimer with a novel structure, has good activity, can be taken as a pilot compound for anti-HBV drugs and has broad application prospects.