An efficient method for the synthesis of phenacyl ester‐protected dipeptides using neutral alumina‐supported sodium carbonate ‘Na 2 CO 3 /n‐Al 2 O 3 ’

• Published in: Journal of peptide science Vol. 19; no. 10; pp. 659 - 662
• Main Authors: Hashimoto, Chikao, Sugimoto, Kazuhiro, Takahashi, Youhei, Kodomari, Mitsuo
• Format: Journal Article
• Language: English
• Published: 01-10-2013
• ISSN: 1075-2617; 1099-1387
• DOI: 10.1002/psc.2544

In the synthesis of dipeptides (Boc‐AA
1
‐AA
2
‐OPac: AA
1
and AA
2
represent amino acids) protected by phenacyl (Pac) ester, amines and solid bases as the base for the conversion of the trifluoroacetic acid (TFA) salt of the amino component (TFA·H‐AA
2
‐OPac) into the corresponding free amino component (H‐AA
2
‐OPac) were examined. The synthesis of a dipeptide (Boc‐Ala‐Gly‐OPac) using amines for the conversion afforded an unsatisfactory yield with by‐products. On the other hand, the use of neutral alumina‐supported Na
2
CO
3
(Na
2
CO
3
/n‐Al
2
O
3
) as a solid base for the conversion provided the dipeptide in a quantitative yield without by‐products. The application of Na
2
CO
3
/n‐Al
2
O
3
to the synthesis of some dipeptides protected by Pac ester gave the desired peptides in excellent yields. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.