Table 1. Apparent Affinities of Pyrido[2,1-f]purine-2,4-dione Derivatives 13–19.
| compound | n | X | R1 | pKi ± SEMa or disp. at 10 μm (%) |
|---|---|---|---|---|
| 13a | 1 | O | 4-SO2F | 6.7 ± 0.1 |
| 13b | 2 | O | 4-SO2F | 7.7 ± 0.1 |
| 13c | 3 | O | 4-SO2F | 7.5 ± 0.1 |
| 14a | 1 | O | 3-SO2F | 6.4 ± 0.1 |
| 14b | 2 | O | 3-SO2F | 7.0 ± 0.05 |
| 14c | 3 | O | 3-SO2F | 7.1 ± 0.05 |
| 17a | 1 | NH | 4-SO2F | 27% |
| 17b (LUF7602) | 2 | NH | 4-SO2F | 8.0 ± 0.05 |
| 17c | 3 | NH | 4-SO2F | 7.5 ± 0.05 |
| 18a | 1 | NH | 3-SO2F | 18% |
| 18b | 2 | NH | 3-SO2F | 7.5 ± 0.01 |
| 18c | 3 | NH | 3-SO2F | 6.8 ± 0.1 |
| 19 (LUF7714) | 2 | NH | 4-SO2Me | 6.3 ± 0.03 |
a
Data are expressed as means ± standard error of the mean (SEM) of three separate experiments each performed in duplicate. Apparent affinity determined from the displacement of specific [3H]PSB-11 binding from the hA3AR stably expressed on Chinese hamster ovary (CHO) cell membranes at 25 °C during 2 h of incubation.