Table 3. Number of NMR Observablesa.
| tetramer | measured NOEs | overlap NOEs | β | γ | ribose | ϵ | total |
|---|---|---|---|---|---|---|---|
| r(AAAA) | 23 | 3 | 3 | 4 | 11 | 3 | 47 |
| r(CAAU) | 42 | 6 | 3 | 4 | 11 | 3 | 69 |
| r(GACC) | 23 | 9 | 3 | 4 | 12 | 3 | 54 |
| r(UUUU) | 1 | 5 | 3 | 3 | 10 | 3 | 25 |
a
Number of measured NOEs depends on how many 1H–1H pairs are visible in the spectrum (cf. Supporting Information Tables 12 and 13). The NOEs (cf. Section 2.3) and 3J scalar coupling allow a direct comparison between NMR results and computational predictions. Overlap NOEs could not be definitively measured in NOESY spectra (cf. Figure 6). Only one NOE was measured with r(UUUU), which is consistent with r(UUUU) being far from an A-form structure. NOEs with H5′ or H5″ were omitted.