Table 3.
In vitro IC50 values against the PANC-1 cell line for natural 2, synthetic 2a, other synthetic analogs, and two therapeutic standards.
| Compound | PANC-1 IC50 (μM) |
|---|---|
| 6-Br-conicamin (1) | NA |
| 6-Br-8-keto-conicamin A (2) [natural product] | 1.5 |
| 6-Br-8-keto-conicamin A (2a) [synthetic product] | 4.1 |
| 5-Br-8-keto-conicamin A (3) | 5.8 |
| 1H-indole-3-carbonyl cyanide (8) | NA |
| 8-keto-tryptamine (10) | NA |
| 6-Br-8-keto-tryptamine (11) | NA |
| 5-Br-8-keto-tryptamine (12) | NA |
| N,N,N-trimethyl 8-keto-tryptamine (13) | 23 |
| 6-Br-N,N-dimethyl-8-keto-tryptamine (14) | NA |
| 5-Br-N,N-dimethyl-8-keto-tryptamine (15) | NA |
| N,N-dimethyl-8-keto-tryptamine (16) | NA |
| 5-fluorouracil | 5.714; 7.0 |
| gemcitabine | 7.215; 0.02* |
NA – compounds inactive in soft-agar disk diffusion assay as shown in Table 1
*
Note that this IC50 was determined after 5 days compared to 48 hr. We have found in our lab (unpublished data) that there is ~250-fold difference in IC50 values between a 24 hr and a 5-day assay for gemcitabine.