Iodination of p-nitrophenyl ethers used as photolabels.
A system for radioactive labeling of compounds of biological interest that, due to their low electronic density, cannot be labeled by the standard iodination techniques is described. Using p-nitroanisole as a model, we have prepared 2-[125I]iodo-4-nitroanisole by treatment with thallium trifluoroacetate, with later displacement of the thallium by iodide according to A. McKillop et al. (J. Amer. Chem. Soc. 93, 4841-4844 (1970)). The labeled iodonitroanisole has been used as a photoactive reagent to label a protein (bovine serum albumin), showing that under the irradiation conditions used, the label is incorporated into the polypeptide mainly through modification of epsilon-amino groups of the lysine residues.
D000840:Anisoles / Q000138:chemical synthesis*; D007457:Iodine Radioisotopes; D007553:Isotope Labeling / Q000379:methods*; D008239:Lysine; D012710:Serum Albumin, Bovine; D012711:Serum Albumin, Radio-Iodinated
D000840:Anisoles; D007457:Iodine Radioisotopes; D012711:Serum Albumin, Radio-Iodinated; D012710:Serum Albumin, Bovine; C037824:2-iodo-4-nitroanisole; D008239:Lysine