Analogs of Nornicotine - an Aldol Catalyst Exemplifying Natural Toxicity

Analogs of Nornicotine - an Aldol Catalyst Exemplifying Natural Toxicity 

However, the usefulness of nicotine alkaloids is highly questionable because of their notorious toxicity. Rogers et al. [58e] also reported that a synthetic 3-nitrophenyl analog of nornicotine gave a greater rate enhancement for the aldol reaction than the natural pyridyl system. However, the choice of investigating 3-pyridines is a curious 

Firstly, although epiboxidine was designed to be far less toxic than the related frog toxin epibatidine, it is still sufficiently hazardous to be an unlikely catalyst. In addition, the poor catalytic activity of epibatidine, as demonstrated by Dickerson and Janda, combined with the requirement for a multistep synthesis, make epiboxidine an 

L-Proline (S)-3-(2-Pyridyl)pyrrolidine (5)-3-(2-Pyridyl)piperidine (S)-3-(2-Pyridyl)tetrazole 

The plane of symmetry bisecting varenicline means that it is meso, rather than chiral. Nevertheless, in combination with a chiral additive such as tartaric acid or camphorsulfonic add (CSA), it may still be possible to achieve asymmetric induction via aminocatalysis. In such a scenario, a nucleophilic enamine formed from varenicline might be desymmetrized by selective protonation of one of the two heteroaromatic nitrogens. Alternatively, the enamine might effect asymmetric induction merely by virtue of the chiral environment resulting from the presence of either one or two chiral camphorsulfonate counterions. However, varenicline 

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