Plant Families Appendix

Nomicotine, an organocatalyst studied by Dickerson and co-workers (Entry 5 [52, 58d], Appendix 7.B), reinforces the important principle that even catalysts from Nature can present problems when it comes to toxicity. The family of nicotinic receptor agonists (Figure 7.9) contains several chiral pyrrolidines and piperidines with the potential to act as asymmetric aldol catalysts. Nomicotine, which can be isolated from plants such as tobacco, or readily synthesized by demethylation of the maj or tobacco alkaloid nicotine, was investigated in some depth as an aldol catalyst by Dickerson and Janda in 2002 [52]. 

The chamisa or chamiso plant is a dense southwestern shmb of the rose family, with the scientific name Adenostomafasciculatum. One may speculate that the plant itself may have anticancer properties, being of the family Rosaceae, which includes almonds and the like, and their amygdaUn or laetrile content. As cited in Appendix U of Hoffman (1999), manbers of Rosaceae also contain diterpene alkaloids. However, reducing the leaves to ash would apparently destroy any bioactive organic constituents.)... 

The bioactivities of precocene I, 7-methoxy-2,2-dimethyl chromene, and precocene II, 6,7-dimethoxy-2,2-dimethyl chromene, are well established (Fig. (7)). These two compounds have been isolated from plants throughout the family Asteraceae [129-136, 154]. The chemical data for these compounds and references for their synthesis are compiled in Appendix IV, Tables 13 and 14. There is a wealth of information on the effects of these compounds on various insect species [42, 137]. For simplicity, we will focus on the effects of precocene II on the susceptible Hemipteran bug, Oncopeltus fasciatus. 

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