Figure 2.

Neuroprotective effects of compounds 1–4 and 6 on β-amyloid (Aβ)-induced death in neuronal cells. Neuroblastoma SH-SY5Y cells were incubated in the absence or presence of 5 µM Aβ for 24 h with and without compounds 1, 4, 6 (10 µM), 2 (5 µM) and 3 (10 and 20 µM) (maximum non-toxic concentrations) added 1 h prior to Aβ incubation. The number of viable cells after drug treatments was measured by the 3–(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay. Each data point represents the mean ± standard error of the mean for four different experiments. **p < 0.01, *p < 0.1 significantly different from Aβ-treated cells.