Table 2.
ACT inhibition (J774A.1 cells), cytotoxic effects (J774A.1 cells), and mammalian AC1, AC2 and AC5 inhibition (HEK293 cells) of phosphorodiamidate prodrugs 9a–9i. The ACT inhibition of prodrugs 9a–9i is compared with the potency of their previously reported[17] regioisomers II (Fig. 2).
| Comp | ACT IC50 [μM][a] | ACT for II[17] IC50 [μM][a] | Viability [%][b] | % FSK (5 μM) Stimulated
Activity[d] |
||||
|---|---|---|---|---|---|---|---|---|
| AC1 | AC2 | AC5 | ||||||
| I [c] | 0.15 ± 0.04 | -- | 93 | 64 ± 9 | 200 ± 45 | 99 ± 8 | ||
|
| ||||||||
| 9a | >10 | 1.82 ± 0.58 | 112 | 61 ± 12 | 99 ± 26 | 79 ± 16 | ||
| 9b | 8.72 ± 1.33 | 1.62 ± 0.36 | 106 | 90 ± 15 | 137 ± 30 | 81 ± 15 | ||
| 9c | >10 | 0.26 ± 0.05 | 103 | 88 ± 14 | 126 ± 33 | 91 ± 9 | ||
| 9d | 0.49 ± 0.10 | 0.68 ± 0.08 | 103 | 71 ± 18 | 150 ± 28 | 87 ± 10 | ||
| 9e | >10 | ND | 101 | 74 ± 13 | 98 ± 16 | 81 ± 17 | ||
| 9f | 5.19 ± 0.76 | 0.45 ± 0.17 | 110 | 79 ± 22 | 139 ± 60 | 73 ± 7 | ||
| 9g | >10 | 4.30 ± 0.29 | 101 | 86 ± 41 | 115 ± 32 | 81 ± 9 | ||
| 9h | >10 | 0.66 ± 0.18 | 101 | 119 ± 15 | 112 ± 28 | 84 ± 5 | ||
| 9i | 13.1 ± 0.80 | ND | 108 | 102 ± 21 | 115 ± 33 | 81 ± 12 | ||
|
| ||||||||
| −FSK | ND | ND | ND | 0 ± 0 | 0 ± 0 | 0 ± 0 | ||
| +FSK | ND | ND | ND | 100 ± 0 | 100 ± 0 | 100 ± 0 | ||
| ST034307 | ND | ND | ND | 0 ± 0 | ND | ND | ||
| SKF83566 | ND | ND | ND | ND | 15 ± 12 | ND | ||
Data represent the mean ± SD of at least three independent experiments; IC50 = concentration of a compound causing a 50% decrease in ACT-induced cAMP accumulation.
Data represent the percentage of cell viability at a fixed prodrug concentration (10 μM) versus untreated control.
Previously published data for compound I, ref. [14].
Data represent the mean ± SD of at least three independent experiments at a fixed prodrug concentration (30 μM).
FSK; forskolin. ND: not determined.