Nonpeptidic Tetrafluorophenoxymethyl Ketone Cruzain Inhibitors as Promising New Leads for Chagas Disease Chemotherapy
摘要:
A century after discovering that file Trypanosoma cruzi parasite is the etiological agent of Chagas disease, treatment is still plagued by limited efficacy, toxicity, and the emergence of drug, resistance. The development of inhibitors of the major T. cruzi cysteine protease, cruzain, has been demonstrated to be a promising drug discovery avenue for this neglected disease. Here we establish that a nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitor Substantially ameliorates symptoms of acute Chagas disease in a mouse model With no apparent toxicity. A high-resolution Crystal Structure confirmed the mode of inhibition and revealed key binding interactions of this novel inhibitor class. Subsequent structure-guided optimization then resulted in inhibitor analogues With improvements in potency despite minimal or no additions in molecular weight. Evaluation Of file analogues in cell Culture showed enhanced activity. These results suggest that nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitors have the Potential to fulfill file Urgent need for improved Chagas disease chemotherapy.
Nonpeptidic Tetrafluorophenoxymethyl Ketone Cruzain Inhibitors as Promising New Leads for Chagas Disease Chemotherapy
摘要:
A century after discovering that file Trypanosoma cruzi parasite is the etiological agent of Chagas disease, treatment is still plagued by limited efficacy, toxicity, and the emergence of drug, resistance. The development of inhibitors of the major T. cruzi cysteine protease, cruzain, has been demonstrated to be a promising drug discovery avenue for this neglected disease. Here we establish that a nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitor Substantially ameliorates symptoms of acute Chagas disease in a mouse model With no apparent toxicity. A high-resolution Crystal Structure confirmed the mode of inhibition and revealed key binding interactions of this novel inhibitor class. Subsequent structure-guided optimization then resulted in inhibitor analogues With improvements in potency despite minimal or no additions in molecular weight. Evaluation Of file analogues in cell Culture showed enhanced activity. These results suggest that nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitors have the Potential to fulfill file Urgent need for improved Chagas disease chemotherapy.
[EN] NONPEPTIDIC INHIBITORS OF CRUZAIN<br/>[FR] INHIBITEURS NON PEPTIDIQUES DE LA CRUAZÏNE
申请人:UNIV CALIFORNIA
公开号:WO2009075778A2
公开(公告)日:2009-06-18
Cruzain is the major cysteine protease of T. cruzi, which is the causative agent of Chagas' disease and is a promising target for the development of new chemotherapy. With the goal of developing potent nonpeptidic inhibitors of cruzain, the Substrate Activity Screening (SAS) method was used to screen a library of protease substrates initially designed to target the homologous human protease cathepsin S. Structure-based design was next used to further improve substrate cleavage efficiency by introducing additional binding interactions in the S3 pocket of cruzain. The optimized substrates were then converted to inhibitors by the introduction of cysteine protease mechanism-based pharmacophores. Inhibitor (38) was determined to be reversible even though it incorporated the vinyl sulfone pharmacophore that is well documented to give irreversible cruzain inhibition for peptidic inhibitors. The previously unexplored β-chloro vinyl sulfone pharmacophore provided mechanistic insight that led to the development of potent irreversible acyl- and aryl- oxymethyl ketone cruzain inhibitors. For these inhibitors, potency did not solely depend on leaving group pTa, with 2,3,5,6-tetrafluorophenoxy methyl ketone (54) identified as one of the most potent inhibitors with a second order inactivation constant of 147,000 s-1M-1. This inhibitor completely eradicated the T. cruzi parasite from mammalian cell cultures and consequently has the potential to lead to new chemo therapeutics for Chagas' disease.
Nonpeptidic Tetrafluorophenoxymethyl Ketone Cruzain Inhibitors as Promising New Leads for Chagas Disease Chemotherapy
作者:Katrien Brak、Iain D. Kerr、Kimberly T. Barrett、Nobuhiro Fuchi、Moumita Debnath、Kenny Ang、Juan C. Engel、James H. McKerrow、Patricia S. Doyle、Linda S. Brinen、Jonathan A. Ellman
DOI:10.1021/jm901633v
日期:2010.2.25
A century after discovering that file Trypanosoma cruzi parasite is the etiological agent of Chagas disease, treatment is still plagued by limited efficacy, toxicity, and the emergence of drug, resistance. The development of inhibitors of the major T. cruzi cysteine protease, cruzain, has been demonstrated to be a promising drug discovery avenue for this neglected disease. Here we establish that a nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitor Substantially ameliorates symptoms of acute Chagas disease in a mouse model With no apparent toxicity. A high-resolution Crystal Structure confirmed the mode of inhibition and revealed key binding interactions of this novel inhibitor class. Subsequent structure-guided optimization then resulted in inhibitor analogues With improvements in potency despite minimal or no additions in molecular weight. Evaluation Of file analogues in cell Culture showed enhanced activity. These results suggest that nonpeptidic tetrafluorophenoxymethyl ketone cruzain inhibitors have the Potential to fulfill file Urgent need for improved Chagas disease chemotherapy.