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Updated: Jul 17, 2026

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
New MultiPEG-conjugated theophylline derivatives: synthesis and pharmacological evaluations
Marina Zacchigna1, Gabriella Di Luca, Francesca Cateni
1Department of Pharmaceutical Science, University of Trieste, Piazzale Europa, 1, 34127 Trieste, Italy. zacchign@units.it
Abstract:
The successful conjugation of active theophylline molecules to two new multifunctional high-molecular weight poly(ethylene glycol) derivatives (MultiPEG) and their pharmacokinetic evaluations are reported. The drug loading was increased up to six times in comparison with commercial PEG of the same molecular weight. A clear increase of the time of persistence within the body and a concomitant improvement of the overall pharmacokinetic properties of those prodrugs were also observed. These studies sustain the use of these new PEG-based polymeric supports as a valuable alternative for an effective drug delivery system.
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