A series of acyclic analogs of natural product Syringolin A （SylA） were designed and synthesized during our synthetic efforts for SylA. These acyclic analogs were prepared through a seven-step linear strategy, with total yields varying from 20%-34% for one type of analogs and 12%-18% for the other. These compounds bear a common structure of peptidyl vinyl amide, which reacts irreversibly with the proteasomal active site ThrlO^γ through Michael-type 1,4-addition. Therefore, these acyclic analogs may function the same way as SylA, as potential 20S proteasome inhibitors.
Computer aided fragment-based lead discovery has been successfully applied to the design of inhibitors of aspartyl protease enzyme β-secretase（BACE1）.A benzimidamide fragment,which binds to the two catalytic aspartic acid residues in the active site of the enzyme,was selected as the starting compound.A novel series of 3-phenethylbenzimidamide inhibitors were designed and synthesized.Although biological evaluation results showed that the compounds displayed poor inhibitory activity towards BACE1,3-phenethylbenzimidamide analogs might be modified as potential BACE1 inhibitors.
A novel series of pyrrolidinone analogs that are designed as Michael addition acceptors to react irreversibly with the proteasome active site Thr1O~γhave been synthesized.Although biological evaluation results show that the compounds display poor inhibitory activity towards the proteasome active sites,pyrrolidinone analogs might still be modified to be potential 20S proteasome inhibitors.
