Shiromodiol diacetate

Other antifeedants such as shiromodiol diacetate (50) have been isolated from Parabenzoin trilobum (syn. Lind-era, Lauraceae). These compounds are active against feeding by polyphagous and oligophagous insects at the 0.05-0.1% level in artificial diets (Mabry and Gill, 1979 Munakata, 1977). 

A. niger also converted shiromodiol diacetate (136) isolated from Neolitsea sericea to 2p hydroxy derivative (137) (Nozaki et al., 1996) (Figure 20.45). 

FIGURE 20.45 Biotransformation of shiromodiol diacetate (136) hy Aspergillus niger. 

Nozaki, H., K. Asano, K. Hayashi, M. Tanaka, A. Masuo, and D. Takaoka, 1996. Biotransformation of shiromodiol diacetate and myli-4(15)-en-9-one hy Aspergillus niger IFO 4407. Proceedings of 40th TEAC, pp. 108-110. 

A number of sesquiterpenes have been demonstrated to have pronounced biological activity ( ) among the non-volatile compounds the sesquiterpene lactones are best known (M) but other oxygenated sesquiterpenes are also known to be active. For example, the role of gossypol, a dimeric sesquiterpene and structurally related compounds has been investigated (21,22). The oxygenated sesquiterpenes, shiromodiol monoacetate and diacetate, from Parabenzoin trilobum (=Lindera triloba Blume) possess potent anti feeding activity toward Spodoptera litura larvae (85). 

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