Abstract
From the smoke of normal blend cigarettes the weak heteroaromatic bases with pKa values below 5 have been isolated by steam distillation followed by precipitation of the bases with hydrochloric acid from ethereal solution. 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, trimethylpyrazine, 2-methyl-6ethylpyrazine, 2,6-diethylpyrazine, a dimethyl-ethylpyrazine, tetramethylpyrazine, and a methyl-furylpyrazine, 2-phenylpyridine, 3-phenylpyridine, two methylquinolines, and three dimethylquinolines have been identified in tobacco smoke, for the first time. Furthermore, 3-vinylpyridine, 3-cyanopyridine, quinoline, 2,3'-dipyridyl, skatol, 2-methyl-5-formylfuran, and a methylbenzofuran have been found.