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(+)-adaline from Cryptolaemus montrouzieri

Figure 3.28 Outline of the formation of adaline and adalinine, fatty acid-derived defensive compounds of Adalia beetles, The structure A is the same as in Figure 3.26. The compounds from Cryptolaemus montrouzieri are evidently of related origin

(+)-adaline from Cryptolaemus montrouzieri

Figure 3.28 Outline of the formation of adaline and adalinine, fatty acid-derived defensive compounds of Adalia beetles, The structure A is the same as in Figure 3.26. The compounds from Cryptolaemus montrouzieri are evidently of related origin in droplets at the ends of hairs covering the body (Plate 4). It has been shown by labelling experiments to be made from oleic acid, which loses four carbon atoms from the carboxylate end, and the amino-acid serine (Attygalle, Blankespoor, Eisner and Meinwald, Proceedings of the National Academy of Sciences USA, 1994, 91, 12790). The route to epil-achnine has been studied in great detail with polydeuterated precursors. For example, fully deuterated stearic acid fed to larvae gave compound A isolated from pupae (Figure 3.29). Another intermediate, B, without deuterium at C-15 was incorporated into epilachnine without loss of deuterium. Therefore the chain is specifically oxidized and cyclized at this carbon atom as shown.

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