title: Protein and peptide labeling with (cyclopentadienyl)tricarbonyl rhenium and technetium.
abstract: A method for labeling proteins and peptides with (methoxycarbonyl cyclopentadienyl)tricarbonyl rhenium and technetium is described. The precursors used for this labeling are conveniently produced from perrhenate and pertechnetate, respectively, using a double ligand transfer reaction. For labeling the lysine residues of the model protein bovine serum albumin, the technetium methyl ester was saponified and then transformed into its N-hydroxysuccinimidyl ester. For the labeling of the model peptides leucine enkephalin, substance P, oxytocin, and the tumor imaging/therapy candidate octreotide, the rhenium methyl ester was saponified and activated using either 1-hydoxybenzotriazole or 1-hydroxy-7-azabenzotriazole. The activation and peptide-coupling reactions were followed using reversed-phase (C18) HPLC and yields averaged approximately 70%.
authors.affiliation: Department of Chemistry, University of Illinois, 461 Roger Adams Laboratory, Box 37-5, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
authors.forename: T W
authors.initials: TW
authors.lastname: Spradau
authors.forename: J A
authors.initials: JA
authors.lastname: Katzenellenbogen
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004743:Enkephalin, Leucine / Q000737:chemistry; D008024:Ligands; D015282:Octreotide / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry*; D015609:Organotechnetium Compounds / Q000737:chemistry*; D010121:Oxytocin / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D011868:Radioisotopes; D019275:Radiopharmaceuticals / Q000737:chemistry*; D012211:Rhenium / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013373:Substance P / Q000737:chemistry; D013667:Technetium / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D015609:Organotechnetium Compounds; D010455:Peptides; D011506:Proteins; D011868:Radioisotopes; D019275:Radiopharmaceuticals; C116454:cyclopentadienyl tricarbonyl rhenium; C116453:cyclopentadienyl tricarbonyl technetium; D012710:Serum Albumin, Bovine; D013373:Substance P; D010121:Oxytocin; D004743:Enkephalin, Leucine; D012211:Rhenium; D013667:Technetium; D015282:Octreotide