Benz -pyrene

The Hiickel rule is strictly applicable only to monocyclic compounds, but the general concept of aromaticity can be extended beyond simple mono-cyclic compounds to include polycyclic aromatic compounds. Naphthalene, with two benzene-like rings fused together, anthracene, 1,2-benz-pyrene, and coronene are all well-known compounds. BenzoLalpyrene is particularly interesting because it is one of the cancer-causing substances that has been isolated from tobacco smoke. 

Lu AYH, West SB. 1972. Reconstituted liver microsomal enzyme system that hydroxylates drugs, other foreign compounds and endogenous substrates. III. Properties of the reconstituted 3,4-benz-pyrene hydroxylase system. Mol. Pharmacol. 8 490-500... 

Cooper, R.L. and A.J. Lindsey The presence of 3,4-benz-pyrene and other polycyclic hydrocarbons in the combustion products of cigarette paper Chem. and Ind. (London) (1954) 1260-1261. 

Poel, W.E. Carcinogens and minimal carcinogenic doses Science 123 (1956) 588 Poel, W.E., D. Stanton, E. Peters, and H.O. Wade Approximation of a threshold-maximal carcinogenic dose range for 3,4-benz-pyrene when applied repeatedly to mouse skin Proc. Am. Assoc. Cancer Res. 4 (2) (1958) 333 Poel, W.E. and A.G. Kammer Preliminary studies in a quantitative approach to skin carcinogenesis J. Natl. Cancer Inst. 16 (1958) 989-994. 

For example, benz[ ]pyrene is epoxidized by the enzyme P-450 monooxygenase and the product epoxide is then opened enzymatically to give a trans diol (Fig. 13.80). 

Figure 3 depicts profiles of Total PAH fluxes vs. time (36). The following polycyclic hydrocarbons have been determined by high performance liquid chromatography, variable wavelength absorption detection Naphthalene, acenaphthylene, 7,12-dimethylbenzanthracene, 2-methylnaphtalene, fluorene, acenaphtene, phenanthrene, 2,3-dimethylnaphtalene, anthracene, fluoranthene, 1-methylphenanthrene, pyrene, 2,3-benzofluorene, triphenylene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, perylene, benzo(e)pyrene, 1,2,3,4-dibenzanthracene, benzo(a)pyrene, and 1,2,5,6-dibenzanthracene. 

Note Bi, biphenyl Nap, naphthalene Phe, phenanthrene Anth, anthracene Hu, fluoranthene Pyr, pyrene Chr, chrysene BaAnth, benz[a]anthracene BaPyr, benzo[a]pyrene BbFlu, benzo[h]fluoranthene DBaAnth, dibenz[a,/i]anthracene 3-Me-Chol, 3-methylcholanthrene. 

Schneider J,RGrosser,KJayasimhulu,WXue,DWarshawsky(1996)Degradationofpyrene,benz[a]anthracene, and benzo[a]pyrene by Mycobacterium sp. strain RGHll-135, isolated from a former coal gasification site. Appl Environ Microbiol 62 13-19. 

A cytochrome P450 has been purified from Saccharomyces cerevisiae that has benzo[a]pyrene hydroxylase activity (King et al. 1984), and metabolizes benzo[fl]pyrene to 3- and 9-hydroxybenzo[fl]pyrene and benzo[fl]pyrene-7,8-dihydrodiol (Wiseman and Woods 1979). The transformation of PAHs by Candida Upolytica produced predominantly monohydroxyl-ated products naphth-l-ol from naphthalene, 4-hydroxybiphenyl from biphenyl and 3- and 9-hydroxybenzo[fl]pyrene from benzo[fl]pyrene (Cerniglia and Crow 1981). The transformation of phenanthrene was demonstrated in a number of yeasts isolated from littoral sediments and of these, Trichosporumpenicillatum was the most active. In contrast, biotransformation of benz[fl]anthracene by Candida krusei and Rhodotorula minuta was much slower (MacGillivray and Shiaris 1993). 

The biodegradation of pyrene, chrysene, fluoranthene, benz[a]anthracene, dibenz[a,/t] anthracene, benzo[a]pyrene, and coronene by Stenotrophomonas maltophilia has been studied in the presence of a range of synthetic surfactants (Boonchan et al. 1998). Nonneutral surfactants were toxic, biodegradation was also inhibited by the neutral Igepal CA-630, and the positive enhancement of removal of substrates was generally low—in the range of 10%. 

In contrast to the three-ring compounds, residues of benz[a]anthracene, chrysene, and benzo[fl]pyrene were found after 15 weeks incubation in compost-amended soil. 

Maier EA, Schimmel H, Hinschberger J, Griepink B, and Jacob J (1994) The certification of the contents (mass fraction) of pyrene, benz[a]anthracene, benzo[o]pyrene, benzo[e]pyrene, benzojb]-fluoranthene, benzo[fe]fluoranthene, indeno[i,2,3-cd]pyrene and benzo[b]naphtho[2,i-d]thiophene in dried sewage sludge. BCR Information, Reference Materials. Report EUR 15039 EN, 51 pp. 

PAHs, more correctly known as polyaromatic compounds (PACs) are common in the human environment, e.g, the exhaust of diesel engines, bitumen and asphalt production. Some of the PAHs are genotoxic and carcinogenic (e.g benz(a)pyrene). 

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. 

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