Table 2. Structure and Activities of Analogs 14a.

| compd | R | hM5 EC50 (nM) (pEC50 ± SEM) | hM5 % ACh Max |
|---|---|---|---|
| 14a | H | >10000 (<5) | <25 |
| 14b | Me | 2535 (5.60 ± 0.03) | 70 ± 5 |
| 14c | n-Pr | 112 (7.08 ± 0.27) | 73 ± 4 |
| 14d | n-Bu | 349 (6.46 ± 0.02) | 77 ± 3 |
| 14e | CD2CH3 | 456 (6.36 ± 0.07) | 74 ± 3 |
hM5 pEC50, and ACh Max data reported as averages ± SEM from our functional calcium assay; n = 3 determinations.