Epoxides benzopyrene

Hydroxylation may also take place at nitrogen atoms, resulting in hydroxyl-amines (e.g., acetaminophen). Benzene, polycyclic aromatic compounds (e.g., benzopyrene), and unsaturated cyclic carbohydrates can be converted by mono-oxygenases to epoxides, highly reactive electrophiles that are hepato-toxic and possibly carcinogenic. 

Water conjugation Water Epoxide hydrolase (microsomes) Arene oxides, cis-disubstituted and mono-substituted oxiranes Benzopyrene 7,8-epoxide, styrene 1,2-oxide, carbamazepine epoxide... 

Estrogens induce tumors in animals, a fact that probably depends on the formation of catechol-type A rings. Arene oxides and/or semiquinones may then be formed, which react as cross-linkers in the same way as polycyclic hydrocarbons, such as benzopyrene, which is oxidized in the body to a diol-epoxide. Electroreduction of the corresponding ortho-quimm to the semiquinone radical, the same product that would be formed upon oxygen oxidation of the catechol, in the presence of adenine, does indeed produce a covalent adduct in 14% yield (Scheme 3.4.5)... 

Other cases are described in Section 13.5 under the heading Lethal examples . Thus fluoroacetic acid is transformed to fluorocitric acid which blocks the enzyme aconitase. Several amines, such as benzidine and 2-aminonaph-thalene are converted to carcinogenic hydroxylamines and polycyclic hydrocarbons such as benzopyrene are converted to carcinogenic epoxides. The liver converts carbon tetrachloride to a free radical which causes liver necrosis (Slater, 1966). 

For example, benzopyrene benzopyrene epoxide. Alcohol oxidation... 

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