Table 1.
Comparison of 1H-NMR dT resonances [a] and UV maxima in adducts 9 and 10 with literature data for methylthymidines.
| N3-methyl-dT [b] | O2-methyl-dT [c] | O4-methyl-dT [d] | N3-NVP-dT (9) | O4-NVP-dT (10) | |
|---|---|---|---|---|---|
| UV(λmax, nm) | 267, 235 [e] | 259, 237 (pH 1) | 280, 241 [f] | 266 [g] | 284 [g] |
| 257, 239 | |||||
| (pH 13) | |||||
| δ (ppm) | |||||
| H1' | 6.27 | 6.08 | 6.24 | 6.17 | 6.66 |
| H2' | 2.14 | 2.12–2.17 | 2.0–2.19 | 2.50 | NA [h] |
| H3' | 3.65–4.76 | 4.19–4.27 | 3.84 | 3.77–3.79 | NA |
| H4' | 3.65–4.76 | 3.70–3.80 | 4.22 | 4.26 | 5.33 |
| H5' | 3.55–3.60 | 3.47–3.66 | 3.59–3.81 | 3.50 | NA |
| H6 | 7.83 | 7.80 | 8.01 | 7.90 | 8.55 |
| dT-CH3 | 1.87 | 1.78 | 1.88 | 1.90 | NA |
[a] The spectra were recorded in DMSO-d6. Chemical shifts are in ppm, downfield from tetramethylsilane; [b] The NMR data are from Kimura et al. [37]; [c] The NMR and UV data are from Huang et al. [38]; [d] The NMR data are from Miah et al. [39]; [e] The UV data, recorded in water, are from Chang et al. [40]; [f] The UV data, recorded in water, are from Lawley et al. [41]; [g] The spectra were obtained online, by HPLC with diode array detection, in acetonitrile/0.1% aqueous formic acid; [h] NA, not assigned.