Figure 7.

Dose-dependent antinociception produced by selected TPI-2213 series compounds. Dose–response lines of morphine and TPI-2213-12, -17, -18, -20, -21, -23, -24, -32, and -54 given by i.p. injection 30 min prior to testing in the mouse 55 °C warm water tail-withdrawal assay. Points = 8 mice each. On the basis of the ED₅₀ (and 95% confidence interval) values (Table 2), each 2213 compound exhibited similar antinociceptive potencies to morphine, with the exception of 2213-54, which displayed approximately half the potency of morphine.