Polycyclic aromatic hydrocarbons diol epoxide mechanism

Abbreviations PAH, polycyclic aromatic hydrocarbon DE, diol epoxide PAHDE, polycyclic aromatic hydrocarbon diol epoxide PAHTC, polycyclic aromatic hydrocarbon triol carbocation TC, triol carbocation BaP, benzo[a]pyrene BeP, benzo[e]pyrene BA, benz[a]anthracene DBA, dibenz[a,h]anthracene BcPh, benzo[c)phenanthrene Ch, chrysene MCh, methylchrysene MBA, 7-methyl benz[a]anthracene DMBA, 7,12-dimethyl benz[a]anthracene EBA, 7-ethyl benz[a]anthracene DB(a,l)P, dibenzo[a,l]pyrene MSCR, mechanism-based structure-carcinogenicity relationship PMO, Perturbational molecular orbital method dA, deoxyadenosine dC, deoxycytosine dG, deoxyguanosine MOS, monoxygenase enzyme system EH, epoxide hydrolase enzyme system N2(G), exocyclic nitrogen of guanine C, electrophilic centre of PAHTC K, intercalation constant CD, circular dichroism LD, linear dichroism. 

Weston, A. Newman, M. J. Mann, D. L. Brooks, B. R. Molecular mechanics and antibody binding in the structural analysis of polycyclic aromatic hydrocarbon diol-epoxide DNA adducts. Carcinogenesis (Lond), 11 859-64. 1990. 

In the pH range of 5 - 10, H20-catalyzed hydrolysis is the predominant mechanism (see Fig. 10.11, Pathway b), resulting in the formation of the (8R,9R)-dihydrodiol (10.133, Fig. 10.30). Thus, aflatoxin B1 exo-8,9-epoxide is possibly the most reactive oxirane of biological relevance. Such an extreme reactivity is mostly due to the electronic influence of 0(7), as also influenced by stereolectronic factors, i.e., the difference between the exo- and endo-epoxides. The structural and mechanistic analogies with the dihydro-diol epoxides of polycyclic aromatic hydrocarbons (Sect. 10.4.4) are worth noting. 

Lewis-Bevan, L., Little, S. B., and Rabinowitz, J. R. (1995). Quanmm mechanical studies of the structure and reactivities of the diol epoxides of benzo[c]phenanthrene. Chem Res Toxicol 8, 499—505. Lodovici, M., Akpan, V., Giovannini, L., Migliani, E., and Dolara, P. (1998). Benzo[a]pyrene diol-epoxide DNA adducts and levels of polycyclic aromatic hydrocarbons in autoptic samples from human... 

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