Table 3. Results of Top1 DNA cleavage assay and cytotoxicity assay.
| List | Compound | CAS-RN1 | Top1 inhibition2 | Cytotoxic activity: GI50 3 |
| 1 | NSC 0674004 | 185216-64-2 | +/++ | Between 15.8 and 100 µM4 |
| 2 | NSC 0661172 | 153621-30-8 | + | >10 µM for all cells4 |
| 2 | NSC 0318814 | 76867-10-2 | + | Between 20.0 and >100 µM5 |
| 2 | NSC 0053340 | 93009-81-5 | + | Between 23.4 and >100 µM5 |
| 2 | NSC 0039875 | 736072-20-1 | +/++ | >100 µM for all cells5 |
| Simil. | NSC 0042379 | 92556-40-6 | + | Between 20.0 and >100 µM5 |
| Control | Camptothecin(CPT, NSC 0094600) | 7689-03-4 | ++++ | Between 10 nM and 1.3 µM4 |
1
Chemical Abstracts Registration Number.
2
Top1 inhibition ranking: 0 (no activity); + (20–50% of 1 µM CPT activity); ++ (50–75% of 1 µM CPT activity); +++ (75–100% of 1 µM CPT activity); ++++ (equipotent or more potent than 1 µM CPT).
3
Cytotoxic activity measured in the US National Cancer Institute (NCI) 60 human tumour cell line anticancer drug screen [47]. GI50 corresponds to the concentration of the drug (molar) resulting in a 50% growth inhibition.
4
determined previously, published on-line (http://dtp.nci.nih.gov/); in case of camptothecin, the data has been averaged from six experiments, for all other compounds, only one experiment has been performed.
5
determined during this work, data from single experiment.