Figure 2

CD spectra of natural TBA and LNA- or OMeNA-substituted TBAs. A, single-substitution in K⁺; B, double-substitution in K⁺; C, four- and eight-substitution in K⁺; D, single-substitution in Ca²⁺; E, double-substitution in Ca²⁺; F, four- and eight-substitution in Ca²⁺. L or M stands for either LNA or OMeNA when the specified residues are substituted, N (N = 1 or 2 or 4 or 8) represents the number of substitutions, and numbers in parentheses represent the modified positions marked in Figure 1A.