Table 5.

Effects of Steroids 1–9 and Steroid Enantiomers ent-1–ent-3 and ent-1–ent-12 on Tadpole Righting and Swimming Reflexes^a

compd	tadpole LRR EC50 (μM)	tadpole LRR nHill	Tadpole LSR EC50 (μM)	Tadpole LSR nHillb
1 c	3.38 ± 0.90	−2.83 ±2.66	Noned	–
ent-1 c	1.42 ± 0.18	−2.17 ±0.48	5.48 ± 0.12	−33 ± 0
2	5.09 ± 2.43	−1.29 ± 1.22	>10	–
ent-2	2.39 ± 0.28	−2.10 ±0.42	>10	–
3	None	–	None	–
ent-3	0.59 ± 0.07	−1.84 ± 0.32	2.94 ± 0	−20 ± 1
4 e	1.44 ± 0.20	−2.84 ± 0.77	5.48 ± 0.20	−33 ± 0
5 f	0.42 ±0.04	−1.83 ± 0.32	5.5 ± 0.5	−7.5 ± 1.1
6 g	1.12 ± 0.14	−3.38 ± 2.28	5.48 ± 0.11	−34 ± 0
7	3.60 ± 1.52	−2.74 ± 3.25	7.54 ± 0	−30 ± 0
ent-7	0.55 ± 0.09	−2.90 ± 0.07	1.73 ± 0.04	−37
8	3.15 ± 0.30	−2.55 ± 0.78	9.29 ± 0.03	−15 ± 1
ent-8	2.91 ± 0.36	−2.37 ± 0.80	10.3 ± 0	−21 ± 0
9	3.15 ± 0.25	−2.60 ± 0.70	13.5 ± 0	−74 ± 0
ent-9	0.34 ± 0.04	−2.75 ± 1.13	1.73 ± 0.03	−36 ± 0
ent-10	3.64 ± 2.17	−4.32 ± 11.8	None	–
ent-11	1.16 ± 0.21	−4.03 ± 4.06	5.48 ± 0.12	−33 ± 0
ent-12	None	–	None	–

^aThe methods are as reported previously.⁴⁶ Error limits are calculated as the standard error of the mean (N = 10 or more animals at each of five or more different concentrations).

^bLSR typically has a very steep concentration–response curve. The reported ⁿHill values vary widely depending on how many animals had LSR at the concentration (typically, 3 μM) preceding the concentration (typically, 10 μM) that produced LSR in all animals. No SAR conclusions were based on these slope values.

^cLiterature values.⁹

^d“None” indicates that all animals had a swimming response at 10 μM test compound.

^eLiterature values. ¹⁵

^fLiterature values. ⁴⁶

^gLiterature values. ⁴⁸