Access to the inaccessible sequence of Cpn 60.1 (195-217) by temporary oxazolidine protection of selected amide bonds

The solid-phase peptide synthesis of a reportedly inaccessible peptide sequ ence of chaperonin 60.1 (195-219) is described using oxazolidine containing dipeptide building blocks ('pseudo-proline' dipeptide units). Two attempts at the synthesis of the chaperonin 60.1 sequence are outlined using one an d two pseudo-proline units, respectively, and these results are compared wi th the outcome of an ordinary stepwise (double) coupling procedure. The onl y successful synthesis is that combining two pseudo-proline building blocks . (C) 2001 Elsevier Science Ltd. AII rights reserved.