7-Hydroxybenzo pyrene

Similarly, with exocyclic O-PACs, substitutive nomenclature and common suffixes are used to describe the O-atom compounds formed when an H-atom on a PAH is replaced by another atom or functional group, e.g., 6-hydroxybenzo[ ]pyrene, XIX, or 2-methoxychrysene, XX ... 

Benzo[o]pyrene-rranj-9,10-dihydrodiol 2) Benzolajpy-rene-/r n.s-4,5-dihydrodiol 3) Benzo oJpyrene-(roiM-7.8-di-hydrodiol 4) 9-HydroxybenzolHydroxy-benzo[a]pyrene 8) Benzo[o]pyrene. 

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). 

Graceffa, P. and Weitzman, S.A. (1987). Asbestos catalyzes the formation of 6-oxobenzo(a)pyrene radical from 6-hydroxybenzo(a)pyrene. Arch. Biochem. Biophys. 257, 481-484. 

Incubation Conditions pmoles 3-hydroxybenzo(a)pyrene formed/min/nmol cytochrome P-448 % Maximum Activity... 

Hydroxybenzo[a]p3n ene, see Benzo[a]pyrene 9-Hydroxybenzo[a]p3n ene, see Benzo[a]pyrene Hydroxybenzoqninone, see Phenol Hydroxy-p-benzoqninone, see 4-Nitrophenol... 

The K-region 4,5-oxide of benzo[a]pyrene 4 is also known to bind to nucleic acid, ° although little is known about the structures of the bound adducts. Interestingly, 9-hydroxybenzo [a] pyrene, a spontaneous isomerization product of the metabolicaUy formed benzo [a] pyrene 9,10-oxide, also binds to DNA on further metabolic action. Although the evidence is largely indirect, the K-region 4,5-oxide of 9-hydroxybenzo [a] pyrene seems to be responsible for this binding. 

Approximately 50% of the benzo[a]pyrene that was intratracheally instilled in hamsters was metabolized in the nose (Dahl et al. 1985). The metabolite produced in the hamster nose included tetrols, the 4,5-, 7,8-, and 9,10-dihydrodiol. quinones, and 3-and 9-hydroxybenzo[a]pyrene. Similar metabolites were detected in nasal and lung tissues of rats inhaling benzo[a]pyrene (Wolff et al. 1989b). The prevalence of quinone production was not seen in hamsters as it was in rats (Dahl et al. 1985 Weyand and Bevan 1987a, 1988). In monkeys and dogs, dihydrodiols, phenols, quinones, and tetrols were identified in the nasal mucus following nasal instillation of benzo[a]pyrene (Petridou-Fischer et al. 1988). in vitro metabolism of benzo[a]pyrene in the ethmoid turbinates of dogs resulted in a prevalence of phenols (Bond et al. 1988). However, small quantities of quinones and dihydrodiols were also identified. 

Metabolism of benzo[a]pyrene in the primary culture of human hepatocytes primarily resulted in the formation of 3-hydroxybenzo[a]pyrene, 4,5-dihydrodiol, 9,10-dihydrodiol, and 7,8-dihydrodiol (Monteith et al. 1987). As the dose of benzo[a]pyrene increased, the amount of metabolites... 

Rat liver microsomes also catalyzed benzo[a]pyrene metabolism in cumene hydroperoxide (CHP)-dependent reactions which ultimately produced 3-hydroxybenzo[a]pyrene and benzo[a]pyrene-quinones (Cavalieri et al. 1987). At low CHP concentrations, 3-hydroxybenzo[a]pyrene was the major metabolite. As CHP concentrations increased, levels of quinones increased and levels of 3- hydroxybenzo[a]pyrene decreased. This effect of varying CHP levels was reversed by preincubating with pyrene. Pyrene inhibited quinone production and increased 3-hydroxybenzo[a]pyrene production. Pretreatment with other PAHs like naphthalene, phenanthrene, and benz[a]anthracene nonspecifically inhibited the overall metabolism. The binding of benzo[a]pyrene to microsomal proteins correlated with quinone formation. This suggested that a reactive intermediate was a common precursor. The effects of pyrene on benzo[a]pyrene metabolism indicated that two distinct microsomal binding sites were responsible for the formation of 3-hydroxybenzo[a]pyrene and benzo[a]pyrene-quinone (Cavalieri et al. 1987). 

Hydroxybenzo[a]pyrene (ArOH) in dimethylformamide with sulphuric acid in the presence of dicyclohexylcarbodiimide at 0°C afforded an 85% yield of the corresponding sodium 0-sulphate after neutralisation and purification on a DEAE column with methanolic elution (ref.44). 

FtGURE 15-6 Total luminescence spectra. In (a), ihe total fluorescence spectrum of a mixture of anthracene and ovalene is shown as a three-dimensional plot. In (b). the total fluorescence spectrum ol 8-hydroxybenzo(a]pyrene is shown as a contour plot. Each line represents a particular fluorescence intensity. (Part a from Y. Taimi et ai.. Anal. Chem.. 1978.50. 936A. Figure 11. p. 948A. Part b adapted from J. H. Rho and J. L. Stewart. Anal. Chem., 1978. 50. 620. Figure 2, p. 622. Copyright 1978 Amencan Chemical Society.)... 

Chrysene raf25 5,6 dihydrodiol I hydroxychrysene 6-hydroxychrysene l-hydroxybenzo(a)pyrene ... 

Dehydrogenation. Recent syntheses of eight isomeric hydroxybenzo[a]pyrenes involved dehydrogenation of ketones to phenols (for example, equation I) as the final step. Pd black (Engelhard) was found to be generally superior to sulfur for this reaction, which was carried out at near reflux in high-quality 1-methyl-naphthalene under argon. The choice of solvent is critical. ... 

Hydroxyaminoquinoline 1-oxide, 437 A -Hydroxyaniline, 169 A -Hydroxyarylacetamide, 159 1-Hydroxybenzo [a]pyrene, 181, 184... 

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