[30293-99-3] · C4H6N2O3 · (S)-3-Hydroxy-5-methyl-2,4-imidazolidinedione · (MW 130.12)
(acyl activating agent for asymmetrically selective peptide synthesis1)
Alternate Name: (-)-3-hydroxy-5-methylhydantoin.
Physical Data: mp 163-164 °C; [a]D -36.0°.
Preparative Method: prepared from alanine (eq 1).1
The reagent activates amino acids through 1,3-Dicyclohexylcarbodiimide (DCC) coupling to the N-hydroximide for subsequent coupling with chiral amino acids. The asymmetric center induces preferential reaction with L-amino acids and high optical purities of L-L-dipeptides can be achieved (eq 2). Enantioselectivity is improved if the 5-methyl group is replaced by isobutyl.1
Kenneth A. Murray
University of Cambridge, UK