Synthesis of a water-soluble analog of 6-methyl-3-N-alkyl catechol labeled with carbon 13: NMR approach to the reactivity of poison ivy/oak sensitizers toward proteins.
A 13-C labeled water soluble derivative of alkylcatechol was synthesized and reacted with human serum albumin in phosphate buffer at pH 7.4 in air to allow a slow oxidation of the catechol into orthoquinone. The formation of several adducts was evidenced by a combination of 13C and 1H-13C correlation NMR. Although some adducts could result from a classical o-quinone formation - Michael type addition, our results suggest that a second pathway, involving a direct reaction of a carbon centered radical with proteins could be an important mechanism in the formation of modified proteins.
D002247:Carbon Isotopes; D002396:Catechols / Q000138:chemical synthesis; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010947:Plants, Toxic; D011809:Quinones / Q000138:chemical synthesis; D012709:Serum Albumin / Q000187:drug effects; D012251:Toxicodendron / Q000737:chemistry*