Table 2.

The EC₅₀ of the ligustrazine-benzoic acid derivatives for protecting damaged PC12 cells.

Compound	Proliferation rate (%)					EC50 (µM)
	60 µM	30 µM	15 µM	7.5 µM	3.75 µM
1a	61.63	58.87	27.69	18.97	4.58	27.359
2a	16.27	25.49	27.48	33.71	15.65	40.715
3a	81.60	77.58	64.50	32.08	30.07	11.467
4a	126.60	117.10	89.76	52.98	31.12	4.249
5a	47.14	36.44	36.01	−7.22	−5.94	45.029
1b	5.50	32.37	−1.76	−8.25	−16.00	90.345
2b	16.91	27.96	6.99	−22.43	−22.76	95.484
3b	27.30	46.91	33.84	11.21	6.44	38.493
4b	6.29	10.84	−2.28	−10.40	−10.73	>100
5b	27.14	0.47	−0.08	−3.71	−5.67	85.723
1c	21.88	21.67	19.32	−1.87	−17.07	73.801
2c	55.78	90.74	96.07	72.74	58.09	5.828
3c	57.72	18.75	9.20	22.27	−1.86	43.909
4c	9.18	12.54	14.28	12.04	7.31	66.230
5c	15.68	27.93	27.45	−7.01	−11.72	68.265
1d	50.28	41.08	22.15	13.55	2.86	37.398
2d	29.07	44.19	37.79	36.63	1.163	33.245
3d	46.79	40.13	41.79	36.13	33.47	22.210
4d	15.27	62.41	51.74	30.06	1.16	29.683
5d	11.50	37.43	23.97	14.19	11.90	46.678
TMP	14.71	12.11	11.76	10.60	9.44	64.459