Nonenzymatic reduction of benzo(a)pyrene diol-epoxides to trihydroxypentahydrobenzo(a)pyrenes by reduced nicotinamide adenine dinucleotide phosphate.
The diol-epoxide r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene is a potent mutagen and possibly the ultimate carcinogenic form of benzo(a)pyrene. A (7/8,9)-trihydroxy-7,8,9,10,10-pentahydrobenzo(a)pyrene is formed from the diol-epoxide r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydroxybenzo(a)pyrene by reduction with reduced nicotinamide adenine dinucleotide phosphate. Its formation is linear with reduced nicotinamide adenine dinucleotide phosphate concentration and does not require the presence of enzyme. A (7,9/8)-trihydroxy-7,8,9,10,10-pentahydrobenzo(a)pyrene is similarly formed from the diol-epoxide r-7,t-8-dihydroxy-c-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene by reduction with reduced nicotinamide adenine dinucleotide phosphate. The structures of the trihydroxypentahydrobenzo(a)pyrenes were established by their ultraviolet absorption and mass spectra and their reaction with potassium triacetylosmate.
Nonenzymatic reduction of benzo(a)pyrene diol-epoxides to trihydroxypentahydrobenzo(a)pyrenes by reduced nicotinamide adenine dinucleotide phosphate. The diol-epoxide r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene is a potent mutagen and possibly the ultimate carcinogenic form of benzo(a)pyrene. A (7/8,9)-trihydroxy-7,8,9,10,10-pentahydrobenzo(a)pyrene is formed from the diol-epoxide r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydroxybenzo(a)pyrene by reduction with reduced nicotinamide adenine dinucleotide phosphate. Its formation is linear with reduced nicotinamide adenine dinucleotide phosphate concentration and does not require the presence of enzyme. A (7,9/8)-trihydroxy-7,8,9,10,10-pentahydrobenzo(a)pyrene is similarly formed from the diol-epoxide r-7,t-8-dihydroxy-c-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene by reduction with reduced nicotinamide adenine dinucleotide phosphate. The structures of the trihydroxypentahydrobenzo(a)pyrenes were established by their ultraviolet absorption and mass spectra and their reaction with potassium triacetylosmate.