BACE1 and early-onset autosomal dominant Alzheimer disease: Kang et al. [48] tested the inhibitory activities of 4a and 4b against ß-secretase (BACE1), which is strongly associated with the onset of Alzheimer’s disease (AD) and had IC50 values of 48.2 ± 1.2 and 17.7 ± 0.8 μM, respectively.