Table 1.
Stabilization of G-quadruplexes and inhibition of telomerase activity by dibenzophenanthroline derivatives
| Compound no. (see Fig. 1) | ΔTm G4 (FRET), 1 μM dye | IC50 telomerase, μM |
|---|---|---|
| 1 | 11.5 | 0.3 |
| 2 | 5.5 | 1.45 |
| 3 | 9.5 | 0.75 |
| 4 | 11.5 | 1 |
| 5 | 12.5 | 0.5 |
| 6 | 10 | 0.9 |
| 7 | 2.5 | 2 |
| 8 | 4.5 | >10 |
| 9 | 19.7 | 0.028 |
The compounds used in this study are shown in Fig. 1 Lower. The stabilization (in °C) was determined from fluorescence emission measurements of the F21T oligonucleotide (0.2 μM strand concentration + 1 μM compound in a 0.1 M LiCl, 10 mM sodium cacodylate pH 7.3 buffer; λexc = 470 nm; λemi = 515 nm). The concentration that gave 50% inhibition of telomerase by TRAP assay is given in μM. Compound 8 gave no inhibition at 10 μM concentration.