Table 1.
Isolated yields and spectral characteristics of coumarin labeled nucleosides 11–12 a
| Compound b | Yield (%) | λex(nm) | ε (cm-1M-1) | λem(nm) | FI (A.U.) |
| 1a | - | 326 | 12487 | 392 | 1955 |
| 11a | 64 | 326 | 9981 | 395 | 2202 |
| 12a | 48 | 325 | 7123 | 392 | 1923 |
| 1b | - | 323 | 3032 | 418 | 2260 |
| 11b c | 59 | 324 | 9033 | 428 | 2420 |
| 12b | 41 | 322 | 10006 | 429 | 2373 |
| 1c | - | 318/349 | 7444 | 417 | 719/930 |
| 11c | 56 | 319/350 | 4713 | 418 | 822/1006 |
| 12c | 44 | 319/350 | 5291 | 416 | 876/1224 |
a products 13a-c were isolated in low yields (max. 15%) and products 14a-c were not isolated
b c = 10-4 M in methanol
c c = 0.5 × 10-4 M in methanol