(R, S) -N-Nitrosoanabasine

(R, S) -N-Nitrosoanabasine (NAB) is a tobacco-specific N-nitrosamine (TSNA) identified in tobacco products and electronic cigarettes. It inhibits the cytochrome P450 (CYP) isoform CYP2A13 metabolism of 4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone (NNK) into 4-oxo-4- (3-pyridyl) butanal (OPB), 4-hydroxy-1- (3-pyridyl) -1-butanone (HPB), and 4-oxo-4- (3-pyridyl) butanoic acid (OPBA), with respective Ki values of 0.23, 0.87, and 0.5 μM. While NAB is not carcinogenic in hamsters, it is carcinogenic in mice.