N-Terminal boc-protecting group

The comparison of Fig. 6b with Fig. 6a impressively illustrates the drastic influence of the N-terminal Boc-protecting group on the preferred conformational state of (L-Met) in TFE. The short oligomers (n = 1-6) of the N-protonated peptides exist in a predominantly unordered form. The CD curves of sequences with n = 7-9 are indicative of the coexistence of statistically coiled and ordered crmformers The discrepancy becomes evident with higher oligomers (n = 10). The deblocked pqitides adopt a P-sheet structure whereas, as mentioned above, the Boc-protected analogs form a partially helical conformation... 

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