•Guided by docking studies, a series of compounds were designed and synthesized.•Enzyme activity, affinity, permeability and cytotoxicity have been evaluated.•Sixteen compounds were found to have μM to sub-μM level activities towards BACE1.•Compound 41 exhibited high activities and the most optimized drug-like profiles.In this work, a series of 2-substituted-thio-N-(4-substituted-thiazol/1H-imidazol-2-yl)acetamide derivatives were developed as β-secretase (BACE-1) inhibitors. Supported by docking study, a small library of derivatives were designed, synthesized and biologically evaluated in vitro. In addition, the selected compounds were tested with affinity (KD) towards BACE-1, blood brain barrier (BBB) permeability and cytotoxicity. The studies revealed that the most potent analog 41 (IC50 = 4.6 μM) with high predicted BBB permeability and low cellular cytotoxicity, could serve as a good lead structure for further optimization.Download high-res image (306KB)Download full-size image

Enterovirus 71 (EV71) is a kind of RNA virus and one of the two causes of Hand, foot and mouth disease (HFMD). Inhibitors that target key components of Ras/Raf/MEK/ERK pathway in host cells could impair replication of EV71. A series of 3-benzyl-1,3-benzoxazine-2,4-diones were designed from a specific MEK inhibitor G8935, by replacing the double bond between C3 and C4 within the coumarin scaffold with amide bond. One compound (9f) showed submicromolar inhibitory activity among the 12 derivatives. Further optimization on 9f led to two active compounds (9k and 9m) with nanomolar bioactivities (55 nM and 60 nM). The results of enzymatic assays also demonstrated that this series of compounds were allosteric inhibitors of unphosphorylated MEK1. The binding mode of compound 9k was predicted by molecular dynamic simulation and the key interactions were same as published MEK1/2 allosteric inhibitors. In the cell-based assays, compounds 9k and 9m could effectively suppress the ERK1/2 pathway, expression of EV71 VP1, and EV71 induced cytopathic effect (CPE) in rhabdomyosarcoma (RD) cells.

•Novel 4-oxo-1,4-dihydro-quinoline-3-carboxamide motif with BACE-1 were reported.•A series of 6-substituted derivatives as novel BACE-1 inhibitors were synthesized.•Compounds 14d and 14e were good drug-like profiles for further modification.In this work, we report a series of new 4-oxo-1,4-dihydro-quinoline-3-carboxamide derivatives as β-secretase (BACE-1) inhibitors. Supported by docking study, a small library of derivatives were designed, synthesized and biologically evaluated in vitro. The studies revealed that the most potent analog 14e (IC50 = 1.89 μM) with low cellular cytotoxicity and high predicted blood brain barrier permeability, could serve as a good structure for further modification.A series of 4-oxo-1,4-dihydro-quinoline-3-carboxamids were designed from 1 as BACE-1 inhibitors, among which 14e exhibited better drugabilities including improved inhibitory potency, low cytotoxicity and possibility to penetrate BBB.