Methane Rearrangement in Natural Compounds

The diterpenoid aquariolide A 45, having an aquariane skeleton, has been isolated from cultured specimens of Erythropodium caibaeroum with the known antimitotic 

Acetophenone is also a convenient sensitizer for the ODPM rearrangement. Bicyclo[2.2.2]oct-7-ene-2,5-diones 53a-c undergo a highly chemoselective ODPM rearrangement under acetophenone-sensitized irradiation (350 nm) to yield 54a,c and 55b, in excellent yields (Table 4.2) [33]. However, phenols 56a,b, which presum- 

60 could be opened via hydrogenolysis or with Me2CuLi to produce pyrrolizidinones 

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