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Reactive intermediates from 3-hydroxybenzo[a]pyrene and its glucuronide.

O Ribeiro·C A Kirkby·P C Hirom·P Millburn
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Abstract

3-Hydroxybenzo[a]pyrene (3-OH-BaP) is oxidized by the horseradish peroxidase/H2O2 system to benzo[a]pyrene-3,6-quinone. In the presence of N-acetylcysteine one other product is also formed. This was identified by its chemical, and u.v., mass and n.m.r. spectral properties as 6-(H-acetyl-cystein-S-yl)-3-hydroxybenzo[a]pyrene (6-NAc-cys-3-OH-BaP). Replacement of the N-acetylcysteine by glutathione leads to the formation of a 3-OH-BaP-glutathione adduct. Enzymic hydrolysis of benzo[a]pyrene-3-glucuronide in the presence of N-acetylcysteine yields, in addition to 3-OH-BaP, a product which co-chromatographs with 6-NAc-cys-3-OH-BaP and has identical chemical and spectral characteristics.

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AcetylcysteineBenzopyrenesChromatography, High Pressure LiquidGlucuronatesHorseradish PeroxidaseMagnetic Resonance SpectroscopyMass SpectrometrySpectrophotometry, UltravioletJournal ArticleResearch Support, Non-U.S. Gov't

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O Ribeiro, C A Kirkby, P C Hirom, P Millburn. 1986. Reactive intermediates from 3-hydroxybenzo[a]pyrene and its glucuronide.. https://doi.org/10.1093/carcin%2F7.3.481

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