(±)-Nicotine is the racemic mixture of the dominant alkaloid found in tobacco plants. It acts as an agonist at neuronal nicotinic acetylcholine receptors (nAChRs; Kis = 481 and 11.1 nM for α3β4 and α4β2 subtypes, respectively) and possesses addictive and teratogenic properties.1 (−)-(S)-Nicotine is significantly more active at binding nAChRs compared to the (+)-(R) antipode, thus nicotine is typically synthesized as (−)-(S)-nicotine with only 0.2-1% of the (+)-(R) isomer present.2
References
1. Zaveri, N., Jiang, F., Olsen, C., et al. Novel α3β4 nicotinic acetylcholine receptor-selective ligands. Discovery, structure-activity studies, and pharmacological evaluation. J. Med. Chem. 53(22), 8187-8191 (2010).
2. Clayton, P., Lu, A., and Bishop, L. The pyrolysis of (−)-(S)-nicotine: Racemization and decomposition. Chirality 22(4), 442-446 (2010).