Chemistry of insect antifeedants from Azadirachta indica. Part 18: Demethylation and methylation of the C-8 position of the decalin portion of azadirachtin

Article abstract of DOI:10.1016/0040-4020(94)01071-7

The degradation of azadirachtin (1) to the demethylated decalin 4 and the subsequent remethylation to the protected fragment 5 are described. The crucial steps in the degradation sequence were the decarbonylation of 14 and the selective removal of the hyd