Synthesis of Novel and Stable 5-Aminolevulinic Acid Derivatives for the Efficient Synthesis of 5-Aminolevulinic Acid Based Prodrugs

The efficient synthesis of two stable, easily handled precursors of 5-aminolevulinate is reported. These precursors are stable to the chemical transformation needed for the synthesis of bioconjugates and can be readily deprotected in good yields.