Labelling of biologically active molecules with a cyclohexadiene tricarbonyl iron unit

摘要

Tricarbonyl cyclohexa-l,3-diene iron(0) derivatives of two biologically active molecules,N-acetyl cysteine and N-acetyl histamine and of a primary amine,n-butylamine,have been prepared by reaction of [tricarbonyl (1-4-eta-5-N-pyridiniocyclohexa-1,3-diene) iron] tetrafluoroborate a precursor of the highly reactive cation [Fe(CO)3(l-5-eta-C6H7)](+),and characterized spec-troscopically.Kinetic studies revealed that the reaction of iV-acetyl histamine and n-butylamine was much faster than the reaction of N-acetyl cysteine.Acid/base titration of metal-carbonyl labelled histamine was achieved by IR spectroscopy and revealed that the imidazole ring substituted by the metal-carbonyl unit was slightly more basic than the parent compound.