title: New methodology for the preparation of 3-hydroxy-2-pyridinone (3,2-HOPO) chelators - Reaction of amines with a novel electrophilic 3,2-HOPO precursor.
abstract: The preparation of the new electrophilic iminium ester mesylate salt 5 and its reaction with primary and secondary amines have been investigated. Aniline, t-butylamine, and secondary amines react with 5 via ring opening to give the corresponding HOPO derivatives in high yields. The usefulness of this methodology has been demonstrated by the preparation of two new di-HOPO derivatives 19 and 21. This method allows the introduction of the HOPO ligand onto a variety of amine platforms without the concomitant formation of an amide bond and provides access to HOPO chelators of increased water solubility.
authors.affiliation: Department of Chemistry and Biochemistry, MSC 3C, New Mexico State University Las Cruces, NM 88003-8001.
authors.forename: Timothy N
authors.initials: TN
authors.lastname: Lambert
authors.forename: Sumathi
authors.initials: S
authors.lastname: Chittamuru
authors.forename: Hollie K
authors.initials: HK
authors.lastname: Jacobs
authors.forename: Aravamudan S
authors.initials: AS
authors.lastname: Gopalan