Solid-Phase Synthesis of Diverse Azapeptides

Significance

Solid-phase synthesis of azapeptides was demonstrated. For example, the azapeptide epoxide 5 was synthesized using the Wang resin supported hydrazine 1 as a key substrate. Peptide 2 was prepared from 1 by a ­standard solid-phase peptide synthesis. Deprotection of the Alloc group of 2 followed by condensation with acid 3 using DIC/HOBt gave resin-supported azapeptide epoxide 4. Cleavage of the azapeptide chain from the resin and deprotection of the tert-butyl group of the side chain were performed at once by TFA to afford the desired azapeptide epoxide 5 in 26% yield (from 1).