%0 Journal Article %A B. TESTA %A P. JENNER %T Circular Dichroic Determination of the Preferred Conformation of Nicotine and Related Chiral Alkaloids in Aqueous Solution %D 1973 %J Molecular Pharmacology %P 10-16 %V 9 %N 1 %X A negative Cotton effect for the pyridinie 1Lb band of aqueous solutions of S-(-)-nicotine, S-(-)-nornicotine, S-(-)-anabasine, S-(-)-methylanabasine in the neutral and monoprotonated (N-alicyclic protonated) forms, and S-(-)-cotinine in its neutral form was measured by circular dichroism. Theoretical and experimental arguments suggest that Snatzke’s sector rule for the 1Lb band of monosubstituted benzene derivatives can be applied to the pyridine derivatives investigated. Two regions of the torsion angle τ[τ = 120-140 degrees (+ anticlinal) and 300-320 degrees (-synclinal)] were found by the use of molecular models to predict a negative Cotton effect for these alkaloids; the results are in good agreement with data obtained by quantum calculations and X-ray crystallography by other workers. %U https://molpharm.aspetjournals.org/content/molpharm/9/1/10.full.pdf