Insect feeding deterrent

Methyl 2-pyrrole carboxylate was transformed in two steps into an N-pyrrolylalanine derivative which was converted into a pyrrolo[l,2-a]pyr-azine after heating under reflux in toluene. Five subsequent steps led to peramine (Scheme 50), a principal insect feeding deterrent, from Acremo-nium iolli (88CC978). 

Sutherland, O.R.W. et al.. Insect feeding deterrent activity of phytoalexin isoflavonoids, Biochem. Syst. Ecol, 8, 73, 1980. 

Russell, G.B. et al., Vestitol a phytoalexin with insect feeding-deterrent activity, J. Chem. Ecol, 4, 571, 1978. 

O. nubilalis diets (Ewete etal., 1996b). We have also isolated nine triterpenes from bark of Lansium domesticum, collected in Borneo (Omar, 2000). These compounds, called lansiolides, including lansiolic acid (Fig. 1.4), have insect feeding-deterrent activity as well as antimalarial activity. 

Russell GB, Sutherland ORW, Hutchins RFN, Christmas PE. 1978. Yestitol A phytoalexin with insect feeding deterrent activity. J Chem Ecology 4 571-579. 

Peramine (352) is a pyrrole alkaloid identified as a major insect feeding deterrent isolated from perennial ryegrass infected with the entophyte Acre-monium lolii. Due to the interesting heterocyclic ring system and biological activity, the synthesis of peramine is attractive [230],... 

Trihydroxy- - Mentha piperita (Famiaceae) insect feeding deterrent]... 

Insect Feeding Deterrents from Semiarid and Arid Land Plants... 

P h y t o c h e m i c a l investigations of plant species of Parthenium, Encelia and Pi coria (Asteraceae) from semi-arid and arid zones of the United States and Mexico has resulted in the isolation and identification of numerous sesquiterpene lactones and benzopyrans that are active insect feeding deterrents. The chemistry, biological effects and possible mode of action of bioactive pseudoguaianolides and chromenes are reviewed. 

The total synthesis of the insect feeding deterrent peramine was accomplished by D.J. Dumas at du Pont laboratories. The Gabriel synthesis was successfully employed in the last steps of the synthesis. The primary alkyl chloride was treated with potassium phthalimide in DMF at 77-82 °C for 1.5h. The resulting A/-alkylphthalimide was cleaved in high yield using the Ing-Manske procedure. 

Rowan, D.D. etal. 1986. Peramine, anovel insect feeding deterrent from ryegrass infected with the endophyte AcrewojHMjM lo-liae Journal of the Chemical Society Chemical Communications 1986 935-936,... 

This reaction provided the key sequence in the synthesis of the insect feeding deterrent peramine... 

Park, J. H. Gatewood, B. M. Ramaswamy, G. N. Naturally occurring quinones and flavonoid dyes for wool Insect feeding deterrents. J. Appl. Polym. Sci. 2005, 98,322-328. 

Schoonhoven, L. M. and Jermy, T. (1977) A behavioural and electrophysiological analysis of insect feeding deterrents. In Crop Protection Agents - Their Biological Evolution (McFarlane, N. R., ed.) pp. 133-146. Academic Press, New York. 

A similar approach has been used to identify insect feeding deterrents (Escoubas et al. 1992). Here, chemical separations of plant extracts are carried out on silica thin-layer chromatography plates. After the separation is complete and solvent is allowed to evaporate from the plates, a thin layer of agar-based artificial diet is poured over the plate. Chemical compounds from the plate then diffuse into the artificial diet. Test subjects then are allowed to feed on the diet-coated plates. Presumably, the areas that are not eaten contain antifeedants, which can later be identified chemically. 

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