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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1983 Nov;80(21):6680–6684. doi: 10.1073/pnas.80.21.6680

Mechanisms of hydroxylation by cytochrome P-450: metabolism of monohalobenzenes by phenobarbital-induced microsomes.

L T Burka, T M Plucinski, T L Macdonald
PMCID: PMC391234  PMID: 6579552

Abstract

The monohydroxylation of halobenzenes by phenobarbital-induced rat liver microsomes was studied. The p-halophenol was found to be the major metabolite from all four halobenzenes; o-halophenol formation decreased as the halogen atom size increased. Vmax for total hydroxylation (ortho and para products) correlated well with the sigma + Hammett constant with a negative rho value. This implies a positively charged intermediate in the rate-determining step. Vmax for either ortho or para hydroxylation alone did not correlate with a Hammett constant, implying that the product-determining step occurs after the rate-determining step. Rate-determining formation of a radical cation intermediate is postulated to explain this data.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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