title: p-Azidophenyl phosphate is a photoactivatable phosphorylating reagent and p-benzoquinone monoimine precursor.
abstract: p-Azidophenyl phosphate (I) has been exposed to ultraviolet light (lambda=313 nm) in aqueous solution with or without Lys. Analysis of the photoproducts by means of UV-VIS, IR, (1)H, (13)C and (31)P NMR spectroscopy has revealed that under irradiation of I inorganic phosphate (P(i)) is released, and p-benzoquinone monoimine (II) and p-benzoquinone (III) have appeared. The electrophilic nature of the intermediate results in a high tendency to react with lysine molecules, whereas the reaction with water is less favourable when I is irradiated in the presence of Lys. The product formed in this case is a phosphoramidate whose structure has been tentatively supported by (31)P NMR spectroscopy. These results imply that a p-azidophenyl phosphate is a highly potent aryl nitrene-precursor, which can be transformed easily into p-benzoquinone monoimine and is able to phosphorylate nucleophilic groups of amino acids. This finding is of great importance for the discussions about the chemical nature of protein photomodification products when p-azidophenyl phosphate derivatives are used as modifying reagents.
authors.affiliation: Novosibirsk Institute of Bioorganic Chemistry, Siberian Division of the Russian Academy of Sciences, Academica Lavrentyeva av. 8, Novosibirsk, 630090, Russia.
authors.forename: P V
authors.initials: PV
authors.lastname: Alekseyev
authors.forename: I V
authors.initials: IV
authors.lastname: Romanova
authors.forename: M M
authors.initials: MM
authors.lastname: Shakirov
authors.forename: T S
authors.initials: TS
authors.lastname: Godovikova
mesh_terms: D016227:Benzoquinones / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007097:Imines / Q000737:chemistry*; D008239:Lysine / Q000737:chemistry; D015394:Molecular Structure; D010755:Organophosphates / Q000737:chemistry*; D010766:Phosphorylation; D012996:Solutions
chemical_list: C454116:4-azidophenyl phosphate; D016227:Benzoquinones; D007097:Imines; D010755:Organophosphates; D012996:Solutions; D008239:Lysine