Table 4. Effect of Replacing the B-Ring.

^aFitted EC₅₀ values are shown for GluN1/GluN2C to two significant digits when potentiation at 30 μM of the test compound exceeded 120% of control; values in parentheses are the fitted maximum response as a percentage of the initial glutamate (100 μM) and glycine (30 μM) response. All data are from 3–14 oocytes from 2–3 frogs. When no effect was found, the lack of effect was confirmed by testing at 100 μM (data not shown, n ≥ 3 oocytes for all compounds).

^bInhibited at GluN1/GluN2A with an IC₅₀ of 18 μM, at GluN1/GluN2B with an IC₅₀ of 7.2 μM, at GluN1/GluN2C with an IC₅₀ of 11 μM, and GluN1/GluN2D with an IC₅₀ of 5.7 μM.