Antifeedant sesquiterpenes

K. Mori and H. Watanabe, Synthesis of both the enantiomers of polygodial, an insect antifeedant sesquiterpene. Tetrahedron, 42 (1986) 273-281. 

Warburganal (65, Figure 3.14) was isolated in 1976 as an antifeedant sesquiterpene of African plants, Warburgia stuhlmannii and W. ugandensis, by Kubo, Nakanishi et al. Our 1989 synthesis of (-)-warburganal (65) is shown in Figure 3.14.45... 

Fig. (6). Insecticidal and antifeedant sesquiterpenes from some Celastrus species...

Fig. (8). Insect antifeedant sesquiterpenes from Elaeodendron buchananii...

Doskotch, R. W., H. Y. Cheng, T. M. Odell, and L. Girard, Nerolidol An antifeeding sesquiterpene alcohol for gypsy moth larvae from Melaleuca leucadendron, J. Chem. EcoL, 6, 845-851 (1980). 

The sesquiterpene pyridine alkaloids have antifeedant and insecticidal activ-ihes. Some alkaloids, such as triptonine B, hypoglaunine B, hyponine B and wilfortrine, have antivirus activity potential. Others, such as emarginatines A-B, E-G and emarginatine, have cytotoxic activity. Ebenifoline and cangorinine have immunosuppressive activity. 

This was demonstrated by Fukumoto and co-workers in a synthesis of (+)-albicanol (251), a sesquiterpene with potent hsh antifeedant properties (272,273). Oxime 248 [prepared from the (+)-Wieland-Miescher ketone 247] was subjected to cycloaddition using sodium hypochlorite and gave isoxazoline 249 in very good yield (Scheme 6.95). Conversion of 249 into (3-hydroxyketone 250 was again accomplished by the reductive hydrolysis sequence using Raney Ni and trimethyl... 

Eudesmanolide sesquiterpene lactones (G6 G6 C40L) include a variety of variously cytotoxic compounds. The antifeedants alantolactone and isoalantolactone (helenin being a mixture of the two) (C6 ] C5 C40L=CH2) are antimicrobial. The pro-apoptotic activity of these compounds may derive from the reactivity of the a-methylene-y-butyrolactone ring... 

Alantolactone (eudesmanolide sesquiterpene lactone) Inula helenium I. spp. (Asteraceae) Insect antifeedant... 

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