Biorational insecticides

Edelson JV, Duthie J, Roberts W (2002) Toxicity of biorational insecticides activity against the green peach aphid, Myzus persicae (Siilzer). Pest Managem Sci 58 255-260 Ehmann A (1974) A-(p-Coumaryl)-tryptamine and A(-fenilyl-tiyptamine in kernels of Zea mays. Phytochemistry 13 1979-1983... 

Schuster, D.J. and Stansly, P.A., Response of two lacewing species to biorational and broad-spectrum insecticides, Phytoparasitica, 28, 297, 2000. 

The herbicide cinmethylin has been reported to be derived Irom the monoterpene backbone of the cineole class of natural products. Indeed, cinmethylin is identical to 1,4-cineole, with the addition of a benzyl ether moiety that was added to lower the volatility of the natural product. Cinmethylin was in fact developed by Shell Chemical during a biorational synthetic program to discover new insecticides that targeted the glycerol-3-phos-phate shuttle. A phytotoxic dioxalane intermediate was identified. Optimization of the monocyclic structures led to rigid bicyclic structures with improved herbicidal activity. Some of the bicyclic structures possessed the basic backbone of the monoterpene cineoles found in nature. 

Five standard approaches to the generation of new areas for agrochemical (and pharmaceutical) research are commonly cited random screening speculative nthesis imitative ("me-too") chemistry biorational design and finally the exploitation of natural products (7). Although this last approach has found much commercial success in the development of novel insecticides (for example the pyrethroids), there are still relatively few examples of herbicides and fungicides which have been discovered in this way. This account describes the development of a new class of fungicides derived from the strobilurin family of natural products and related compounds, all of which are derivatives of P-methoxyacrylic acid. 

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