Table 2.
Antiproliferative activity of compounds 1–16 in gastric carcinoma cells: EPG85-257P (parental), EPG85-257RNOV (multidrug resistance [MDR] phenotype), and EPG85-257RDB (multidrug resistance [MDR] phenotype).
| Compound | EPG85-257P | EPG85-257RNOV | EPG85-257RDB | ||
|---|---|---|---|---|---|
| IC50 ± SD (μM) | IC50 ± SD (μM) | RRa | IC50 ± SD (μM) | RRa | |
| Epoxylathyrol (1) | >100 | > 100 | — | 70.53 ± 6.24 | < 0.70 |
| Epoxyboetirane E (2) | 19.67 ± 1.56 | 9.97 ± 0.38 | 0.50 | 6.40 ± 0.68 | 0.32 |
| Epoxyboetirane L (4) | >100 | 38.17 ± 2.39 | <0.38 | 21.13±1.76 | < 0.21 |
| Epoxyboetirane M (5) | >25 b | 10.53 ± 0.44 | <0.42 | 4.74 ± 0.21 | < 0.19 |
| Epoxyboetirane N (6) | 39.67 ± 4.88 | 10.62 ± 0.64 | 0.27 | 4.56 ± 0.47 | 0.12 |
| Epoxyboetirane O (7) | >100 | 21.41 ± 1.35 | <0.21 | 50.91 ± 4.95 | < 0.50 |
| Epoxyboetirane P (8) | 7.81 ± 2.01 | 5.91 ± 1.15 | 0.76 | 0.72 ± 0.08 | 0.09 |
| Epoxyboetirane Q (9) | >25 b | >25 b | — | 7.15 ± .1.24 | < 0.28 |
| Epoxyboetirane R (10) | 21.08. ± 2.53 | 10.73 ± 1.36 | 0.50 | 6.63 ± 0.97 | 0.31 |
| Epoxycarbamoylboetirane B (11) | >100 | 78.13 ± 3.69 | <0.78 | 2.59 ± 0.39 | < 0.03 |
| Methoxyboetirane B (15) | 12.52 ± 1.15 | 5.89 ± 0.62 | 0.47 | 3.39 ± 0.44 | 0.27 |
| Methoxyboetirane C (16) | 10.12 ± 0.68 | 8.25 ± 1.49 | 0.82 | 3.98 ± 0.31 | 0.39 |
| Etoposide | 0.105 ± 0.0 | 1.55 ± 0.1 | 14.8 | 6.2 ± 0.3 | 59 |
| Cisplatin | 4.4 ± 0.4 | 2.6 ± 0.2 | 0.6 | 4.0 ± 0.3 | 1 |
| DMSO (2%) | >100 | >100 | — | >100 | — |
aRelative resistance ratio, RR = IC50(resistant)/IC50(parental)); babove this concentration the compound crystallized in the culture medium. For compounds 3, 12, 13 and 14 the IC50 values were found to be above 100 µM against the parental and both resistant cells. Each IC50 value indicates the mean ± SD of n = 3 to 4 independent experiments (each concentration was performed in triplicate per experiment).