Isolation and structural identification of a direct-acting mutagen derived from N-nitroso-N-methylpentylamine and Fenton's reagent with copper ion

Motofumi Miura, Keiko Inami, Masafumi Yoshida, Kentaro Yamaguchi, Tadahiko Mashino, Masataka Mochizuki

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

N-Nitrosodialkylamines show their mutagenicity by forming α-hydroxynitrosamines in the presence of rat S9 mix in the Ames assay. The hydroxyl radical derived from Fe 2+-H 2O 2 (Fenton's reagent) with Cu 2+ activates N-nitrosamines, with an alkyl chain longer than a propyl constituent, to a direct-acting mutagen. The reactivity of Fe 2+-Cu 2+-H 2O 2 on nitrosamines in relation to their metabolic activation is not fully characterized. Here, we report the identification of the direct-acting mutagen derived from N-nitroso-N-methylpentylamine (NMPe) in the presence of Fe 2+, Cu 2+, H 2O 2 and nitric oxide (NO), which is a product of nitrosamine metabolism. A dichloromethane extract of the NMPe reaction mixtures was fractionated by silica gel column chromatography several times and by a preparative high performance liquid chromatography (HPLC); we obtained white crystals as a product. The direct-acting mutagen that was isolated was provisionally identified as 5-ethyl-5-nitro-1-pyrazoline 1-oxide by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy and X-ray crystallography. To confirm the structure of the mutagen, the authentic compound was synthesized from 2-nitrobutene and diazomethane, followed by N-oxidation with m-chloroperoxybenzoic acid. The 1H NMR spectral data from the direct-acting mutagen that was synthesized was identical to the data from the isolated mutagen. Furthermore, the authentic 5-ethyl-5-nitro-1-pyrazoline 1-oxide was mutagenic in Salmonella typhimurium TA1535. The results showed that 5-ethyl-5-nitro-1-pyrazoline 1-oxide was a direct-acting mutagen derived from the reaction of NMPe and Fe 2+-Cu 2+-H 2O 2-NO.

Original languageEnglish
Pages (from-to)5693-5697
Number of pages5
JournalBioorganic and Medicinal Chemistry
Volume19
Issue number18
DOIs
Publication statusPublished - 2011 Sep 15

Keywords

  • Fenton's reagent
  • Hydroxyl radical
  • Metabolic activation
  • N-Nitrosodialkylamine
  • Nitric oxide
  • Pyrazoline

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Medicine
  • Molecular Biology
  • Pharmaceutical Science
  • Drug Discovery
  • Clinical Biochemistry
  • Organic Chemistry

Fingerprint Dive into the research topics of 'Isolation and structural identification of a direct-acting mutagen derived from N-nitroso-N-methylpentylamine and Fenton's reagent with copper ion'. Together they form a unique fingerprint.

  • Cite this