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Updated: May 8, 2026

Synthesis and Bioconjugation of Thiol-Reactive Reagents for the Creation of Site-Selectively Modified Immunoconjugates
Published on: March 6, 2019
The synthesis of biologically relevant conjugates of Re(CO)3 using pyridine-2-carboxyaldehyde
Roshinee Costa1, Kullapa Chanawanno, James T Engle
1Department of Chemistry, University of Akron, Akron, OH 44325-3601, USA.
Abstract:
The new pyridine-2-carboxaldehyde adduct, Re(CO)3(NC6H5C(O)H)Cl 1, and previously reported complex Re(CO)3(NC6H5C(O)H)Br 2 react with aniline derivatives sulfanilamide or 4-aminofluorescein in methanol giving Schiff base conjugates Re(CO)3(pyca-R)X (pyca = pyridinecarbaldehyde imine, X = Cl, Br), 3-6. Pre-isolation of compounds 1 and 2 provides a convenient method for preparing conjugate complexes in addition to the known methods of ligand synthesis and one-pot reactions. All new compounds were completely characterized, and compound 1 and the sulfanilamide derivatives 3 and 4 were structurally elucidated by X-ray crystallography.
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