Quantitative structure-activity relationships of 34 pyrrolidine-modified nicotine agonists are investigated for their binding affinity toward neuronal nicotinic acetylcholine receptor. The results indicate that a large substituent at the R1, R2, and R3 position is detrimental to the binding affinity. Likewise, a large substituent at the R2 alpha or R3 alpha position as well as a hydrogen bond accepting substituent at the R2 beta position are not beneficial to the binding.