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Updated: Jul 6, 2026

Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
A cation-directed switch of intermolecular spin-spin interaction of guanosine derivatives functionalized with
Carla Graziano1, Stefano Masiero, Silvia Pieraccini
1Alma Mater Studiorum, Università di Bologna, Dipartimento di Chimica Organica A. Mangini, Bologna, Italy.
Abstract:
The guanosine derivative 1 functionalized with the persistent radical unit 4-carbonyl-2,2,6,6-tetramethylpiperidin-1-oxyl in solution has no particular intermolecular spin-spin interactions; however, in the presence of potassium ions this compound can form a D4-symmetric octameric assembly [1(8)K]+ in which the nitroxyl moieties show a weak electron spin-spin exchange interaction. Since the relative geometry of the radicals is the outcome of K+-directed self-assembly, the spin-spin interaction can be suppressed by removing the alkaline ion.
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