An Optimized and Universal Protocol for the Synthesis of Morpholine-2,5-Diones from Natural Hydrophobic Amino Acids and Their Mixture

Morpholine-2,5-diones (MDs) are increasingly attractive compounds that can be produced using amino-acid (AA) as starting material. These compounds can undergo polymerisation to produce biodegradable materials, namely polydepsipeptides, that hold the potential to be used in medicinal applications. In this study, a simplified yet high yield MD synthesis procedure was developed and applied to produce a range of MDs derived from hydrophobic AA including Leu, Ile, Val, Phe, Asp(OBzl), Lys(Z) and Ser(tBu). Moreover, using a blend of hydrophobic aminoacids (Leu, Ile, Val, Phe), mixtures of MDs could be synthesised simultaneously. Finally, the polymerisation of these MDs mixtures was probed and proven successful. The concept investigated herein constitutes a novel path towards the valorisation of protein rich waste by producing renewable and biodegradable materials.