Antagonists for the ATP-gated ion channel receptor P2X1 have potential as antithrombotics and for treating hyperactive bladder and inflammation. In this study, salicylanilide derivatives were synthesized based on a screening hit. P2X1 antagonistic potency was assessed in 1321N1 astrocytoma cells stably transfected with the human P2X1 receptor by measuring inhibition of the ATP-induced calcium influx. Structure-activity relationships were analyzed, and selectivity versus other P2X receptor subtypes was assessed. The most potent compounds, N-[3,5-bis(trifluoromethyl)phenyl]-5-chloro-2-hydroxybenzamide (1, IC50 0.0192 mu M) and N-[3,5-bis(trifluoromethyl)phenyl]-4-chloro-2-hydroxybenzamide (14, IC50 0.0231 mu M), displayed >500-fold selectivity versus P2X2 and P2X3, and 10-fold selectivity versus P2X4 and P2X7 receptors, and inhibited collagen-induced platelet aggregation. They behaved as negative allosteric modulators, and molecular modeling studies suggested an extracellular binding site. Besides selective P2X1 antagonists, compounds with ancillary P2X4 and/or P2X7 receptor inhibition were discovered. These compounds represent the first potent, non-acidic, allosteric P2X1 receptor antagonists reported to date.
Novel derivatives of nitro-substituted salicylic acids: Synthesis, antimicrobial activity and cytotoxicity
Inspired by the high antituberculous activity of novel nitro-substituted derivatives and based on promising predicted ADMET properties we have synthesized a series of 33 salicylanilides containing nitro-group in their salicylic part and evaluated them for their in vitro antimycobacterial, antimicrobial and antifungal activities. The presence of nitro-group in position 4 of the salicylic acid was found to be beneficial and the resulting molecules exhibited minimum inhibitory concentrations (MICs) ranging from 2 to 32 mu M against Mycobacterium tuberculosis. The best activity was found for 2-hydroxy-4-nitro-N-[4-(trifluoromethyl)phenyl] benzamide (MIC = 2 mu M). 4-Nitrosalicylanilides were also found to be active against all Staphylococcus species tested while for MRSA strain 2-hydroxy-4-nitro-N-[4-(trifluoromethyl)phenyl] benzamide's MIC was 0.98 mu M. None of the nitrosalicylanilides was active against Enterococcus sp. J 14365/08 and no considerable activity was found against Gram-negative bacteria or fungi. The hepatotoxicity of all nitrosalicylanilides was found to be in the range of their MICs for HepG2 cells. (C) 2015 Elsevier Ltd. All rights reserved.
Allosteric inhibitors of the main protease of SARS-CoV-2
作者:Subodh Kumar Samrat、Jimin Xu、Xuping Xie、Eleonora Gianti、Haiying Chen、Jing Zou、Jason G. Pattis、Khaled Elokely、Hyun Lee、Zhong Li、Michael L. Klein、Pei-Yong Shi、Jia Zhou、Hongmin Li