Development of oligoarginine–drug conjugates linked to new peptidic self-cleavable spacers toward effective intestinal absorption

We designed and synthesized new peptidic self-cleavable spacers that released a parent drug via succinimide formation and the oligoarginine-based cargo-transporter (OACT) system. The self-cleavable efficacy of these compounds was studied and the conversion time was controlled by an amino acid side-chain structure next to the succinyl moiety on the spacer. These novel self-cleavable spacers are promising for developments of the OACT system as means to potentially enhance intestinal absorption of parent drugs.