Polygalacin D2 demonstrated promising binding to key proteins involved in the etiology of AD such as NMDA, BACE1, and synapsin III, II, and I, showing the lowest Gibbs free energy value of −7.755, −7.298, −5.882, −6.011, and −6.742 Kcal/mol, respectively. The gene discussed is BACE1; the disease is Alzheimer disease.