Dibenzo pyrene General

Methods for the synthesis of the biologically active dihydrodiol and diol epoxide metabolites of both carcinogenic and noncarcinogenic polycyclic aromatic hydrocarbons are reviewed. Four general synthetic routes to the trans-dihydrodiol precursors of the bay region anti and syn diol epoxide derivatives have been developed. Syntheses of the oxidized metabolites of the following hydrocarbons via these methods are described benzo(a)pyrene, benz(a)anthracene, benzo-(e)pyrene, dibenz(a,h)anthracene, triphenylene, phen-anthrene, anthracene, chrysene, benzo(c)phenanthrene, dibenzo(a,i)pyrene, dibenzo(a,h)pyrene, 7-methyl-benz(a)anthracene, 7,12-dimethylbenz(a)anthracene, 3-methylcholanthrene, 5-methylchrysene, fluoranthene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)-fluoranthene, and dibenzo(a,e)fluoranthene. 

These hexacyclic hydrocarbons are generally recognized as two of the most potent unsubstituted carcinogenic PAH (38). The 3,4-dihydro-diol of dibenzo(a,i)pyrene (17) and the 1,2-dihydrodiol of dibenzo-(a,h) pyrene (lg) have been synthesized from 4-oxo-l,2,3,4-tetra-hydrodibenzo(a,i)pyrene and 1-oxo-l,2,3,4-tetrahydrodibenzo(a,h)py-rene, respectively, by Method I. (69). Treatment of these dihydro-diols with m-chloroperbenzoic acid gave the corresponding anti diol epoxides (66). 

---