Design, synthesis, and cholinesterase inhibition assay of liquiritigenin derivatives as anti-Alzheimer's activity

Research progress of natural products and their derivatives against Alzheimer's disease

Alzheimer's disease (AD), a persistent neurological dysfunction, has an increasing prevalence with the aging of the world and seriously threatens the health of the elderly. Although there is currently no effective treatment for AD, researchers have not given up, and are committed to exploring the pathogenesis of AD and possible therapeutic drugs. Natural products have attracted considerable attention owing to their unique advantages. One molecule can interact with multiple AD-related targets, thus having the potential to be developed in a multi-target drug. In addition, they are amenable to structural modifications to increase interaction and decrease toxicity. Therefore, natural products and their derivatives that ameliorate pathological changes in AD should be intensively and extensively studied. This review mainly presents research on natural products and their derivatives for the treatment of AD.

Flavonoids from the roots and rhizomes of Sophoratonkinensis and their in vitro anti-SARS-CoV-2 activity

Acute respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had caused a global pandemic since 2019, and posed a serious threat to global health security. Traditional Chinese medicine (TCM) has played an indispensable role in the battle against the epidemic. Many components originated from TCMs were found to inhibit the production of SARS-CoV-2 3C-like protease (3CLpro) and papain-like protease (PLpro), which are two promising therapeutic targets to inhibit SARS-CoV-2. This study describes a systematic investigation of the roots and rhizomes of Sophora tonkinensis, which results in the characterization of 12 new flavonoids, including seven prenylated flavanones (1-7), one prenylated flavonol (8), two prenylated chalcones (9-10), one isoflavanone (11), and one isoflavan dimer (12), together with 43 known compounds (13-55). Their structures including the absolute configurations were elucidated by comprehensive analysis of MS, 1D and 2D NMR data, and time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculations. Compounds 12 and 51 exhibited inhibitory effects against SARS-CoV-2 3CLpro with IC₅₀ values of 34.89 and 19.88 μmol·L^-1, repectively while compounds 9, 43 and 47 exhibited inhibitory effects against PLpro with IC₅₀ values of 32.67, 79.38, and 16.74 μmol·L^-1, respectively.

Combined computational approaches for developing new anti-Alzheimer drug candidates: 3D-QSAR, molecular docking and molecular dynamics studies of liquiritigenin derivatives

Butyrylcholinesterase is an acetylcholine-degrading enzyme involved in the memorization process, which is becoming an interesting target for the symptomatic treatment of Alzheimer's disease. In the present investigation, the structure-activity relationship of a set of Liquiritigenin derivatives recently revealed to be Butyrylcholinesterase inhibitors was studied basing on comparative field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMISA). As a result, performant models with high predictive capability have been developed (CoMFA model: R² = 0.91, Q² = 0.62, R² _pred = 0.85; CoMISA model: R² = 0.92, Q² = 0.59, R² _pred = 0.83) and implemented to design new Liquiritigenin derivatives with improved activity. Besides, the affinity of the designed derivatives towards the active site of Butyrylcholinesterase, was confirmed by molecular docking and molecular dynamics studies. Moreover, they exhibited good pharmacokinetics properties. Accordingly, the outcomes of the present investigations can provide important direction for the development of new anti-Alzheimer's drug candidates.