Critical chain length for helix formation in L‐methionine oligopeptides

The circular dichroism of a series of L ‐methionine oligopeptides [BOC‐(Met) n ‐OMe] was examined in trifluoroethanol and hexafluoroacetone sesquihydrate. The results indicate that the trimer through the hexamer exists predominantly in disordered conformations in these solvents. An abrupt change in the CD pattern at the heptamer in trifluoroethanol suggests that L ‐methionine oligopeptides begin forming helices at this chain length.