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A stable hyponitrite-bridged iron porphyrin complex.

ABSTRACT: The coupling of two nitric oxide (NO) molecules in heme active sites is an important contributor to the conversion of NO to nitrous oxide (N(2)O) by heme-containing enzymes. Several formulations for the presumed heme-Fe{N(2)O(2)}(n-) intermediates have been proposed previously, however, no crystal structures of heme-Fe{N(2)O(2)}(n-) systems have been reported to date. We report the first isolation and characterization of a stable bimetallic hyponitrite iron porphyrin, [(OEP)Fe](2)(mu-N(2)O(2)), prepared from the reaction of [(OEP)Fe](2)(mu-O) with hyponitrous acid. Density functional theoretical calculations were performed on the model compound [(porphine)Fe](2)(mu-N(2)O(2)) to characterize its electronic structure and properties.

SUBMITTER: Xu N

PROVIDER: S-EPMC2676163 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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A stable hyponitrite-bridged iron porphyrin complex.

Xu Nan N Campbell Adam L O AL Powell Douglas R DR Khandogin Jana J Richter-Addo George B GB

Journal of the American Chemical Society 20090201 7

The coupling of two nitric oxide (NO) molecules in heme active sites is an important contributor to the conversion of NO to nitrous oxide (N(2)O) by heme-containing enzymes. Several formulations for the presumed heme-Fe{N(2)O(2)}(n-) intermediates have been proposed previously, however, no crystal structures of heme-Fe{N(2)O(2)}(n-) systems have been reported to date. We report the first isolation and characterization of a stable bimetallic hyponitrite iron porphyrin, [(OEP)Fe](2)(mu-N(2)O(2)), ...[more]

PMID: 19191487

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