Throughout this work, we demonstrate that γfunctional ITLs can be conveniently prepared by use of the appropriate glycidol precursor. We synthesized and characterized a set of γ-functional ITLs and studied the reactivity of a chosen example (allylfunctional ITL) towards model amines, peptides and a protein. Both reaction pathways -single and double modification-that ITLs undergo are explored and the precise control over the reaction trajectory of this reagent is demonstrated. Overall, the presented synthetic strategy introduces a new reactive handle to the ITL heterocycle, which could enable its broader use in polymer and (bio)material sciences as highly efficient ligation for biological substrates.