Limonoids with intact ring systems

Figure 4. Limonoids with intact ring systems...

Limonoids with Intact Ring Systems. These are also closely related to the tetracyclic triterpenoids. Representatives of these compounds are azadirone, 10, azadiradione, 23, epoxyazadiradione, 26 (77), azadiradione-7-benzoate, 24, meldenin, 25 (7 ), vilasinin, 27, and vilasinintriacetate, 28 (79). These limonoids have an intact D ring, but have been oxidized to include an epoxide ring at C-14 and C-15. 

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