Enantiomerization during Reactions of Activated -Alkoxycarbonylamino Acids with Amino Acid Anions

20 ENANTIOMERIZATION DURING REACTIONS OF ACTIVATED N-ALKOXYCARBONYLAMINO ACIDS WITH AMINO ACID ANIONS 

NL Benoiton, YC Lee, R Steinauer. Determination of enantiomers of histidine, arginine and other amino acids by HPLC of their diastereomeric Af-ethoxycarbonyldipep-tides. Pept Res 8, 108, 1995. 

Activated compound 1.0 NaHC03 1.0 Valine 1.0 Na2C03 1.0 Valine 0.75 Na2C03 1.55 Valine 

FIGURE 4.17 Enantiomerization data for reactions of activated IV-alkoxycarbonyl-L-amino acids with an amino acid anion.71,72 Percentage -d-d- peptide formed in reaction with H-d-Val-CL-Na+ in dimethylformamide-water (4 1) at 23°C. 

NL Benoiton, FMF Chen. Activation and racemization in peptide bond formation, in GR Marshall, ed. Peptides Chemistry and Biology. Proceedings of the 10th American Peptide Symposium, Escom, Leiden, 1988, pp 152-155. 

---