Pseudo proline dipeptides

摘要

Disclosed is a process for the manufacture of pseudo proline dipeptides of the formula wherein R¹ is a side chain of an alpha amino acid, R² is an amino protecting group and R³ and R⁴ are independently either hydrogen or C_1-4-alkyl, and R⁵ is hydrogen or methyl starting from an amino acid derivative of the formula wherein R¹ and R² are as defined above. Pseudo proline dipeptides can be used as reversible protecting groups for Ser, Thr and Cys and thus are versatile tools in peptide chemistry.