title: A highly efficient oxidative condensation reaction for selective protein conjugation.
abstract: We hereby report a mild and efficient coupling reaction between alkyl aldehydes and aryl diamines. In the presence of a Cu(2+) or a Zn(2+) ion, oxygen (O2) in air is able to promote the oxidative condensation of the two readily preparable functional groups, forming stable benzimidazole linkages in neutral aqueous solution at room temperature (RT). We demonstrated that the reaction could be utilized to label a T4 lysozyme protein containing a chemically installed aryl diamine group with a fluorescent aldehyde dye molecule at 37 °C.
authors.affiliation: Department of Chemistry, University of California Riverside, 501 Big Springs Road, Riverside, CA 92521, USA. huiwang.ai@ucr.edu.
authors.forename: Ao
authors.initials: A
authors.lastname: Ji
authors.forename: Wei
authors.initials: W
authors.lastname: Ren
authors.forename: Hui-wang
authors.initials: HW
authors.lastname: Ai
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis* / Q000378:metabolism; D001562:Benzimidazoles / Q000138:chemical synthesis / Q000378:metabolism; D003959:Diamines / Q000138:chemical synthesis* / Q000378:metabolism; D009113:Muramidase / Q000138:chemical synthesis* / Q000378:metabolism; D010084:Oxidation-Reduction; D017433:Protein Structure, Secondary
chemical_list: D000447:Aldehydes; D001562:Benzimidazoles; D003959:Diamines; C031000:benzimidazole; D009113:Muramidase