TY - JOUR
T1 - Optimization of N-benzoylindazole derivatives as inhibitors of human neutrophil elastase
AU - Crocetti, Letizia
AU - Schepetkin, Igor A.
AU - Cilibrizzi, Agostino
AU - Graziano, Alessia
AU - Vergelli, Claudia
AU - Giomi, Donatella
AU - Khlebnikov, Andrey Ivanovich
AU - Quinn, Mark T.
AU - Giovannoni, Maria Paola
PY - 2013/8/8
Y1 - 2013/8/8
N2 - Human neutrophil elastase (HNE) is an important therapeutic target for treatment of pulmonary diseases. Previously, we identified novel N-benzoylindazole derivatives as potent, competitive, and pseudoirreversible HNE inhibitors. Here, we report further development of these inhibitors with improved potency, protease selectivity, and stability compared to our previous leads. Introduction of a variety of substituents at position 5 of the indazole resulted in the potent inhibitor 20f (IC50 ∼10 nM) and modifications at position 3 resulted the most potent compound in this series, the 3-CN derivative 5b (IC50 = 7 nM); both derivatives demonstrated good stability and specificity for HNE versus other serine proteases. Molecular docking of selected N-benzoylindazoles into the HNE binding domain suggested that inhibitory activity depended on geometry of the ligand-enzyme complexes. Indeed, the ability of a ligand to form a Michaelis complex and favorable conditions for proton transfer between Hys57, Asp102, and Ser195 both affected activity.
AB - Human neutrophil elastase (HNE) is an important therapeutic target for treatment of pulmonary diseases. Previously, we identified novel N-benzoylindazole derivatives as potent, competitive, and pseudoirreversible HNE inhibitors. Here, we report further development of these inhibitors with improved potency, protease selectivity, and stability compared to our previous leads. Introduction of a variety of substituents at position 5 of the indazole resulted in the potent inhibitor 20f (IC50 ∼10 nM) and modifications at position 3 resulted the most potent compound in this series, the 3-CN derivative 5b (IC50 = 7 nM); both derivatives demonstrated good stability and specificity for HNE versus other serine proteases. Molecular docking of selected N-benzoylindazoles into the HNE binding domain suggested that inhibitory activity depended on geometry of the ligand-enzyme complexes. Indeed, the ability of a ligand to form a Michaelis complex and favorable conditions for proton transfer between Hys57, Asp102, and Ser195 both affected activity.
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U2 - 10.1021/jm400742j
DO - 10.1021/jm400742j
M3 - Article
C2 - 23844670
AN - SCOPUS:84881450780
VL - 56
SP - 6259
EP - 6272
JO - Journal of Medicinal Chemistry
JF - Journal of Medicinal Chemistry
SN - 0022-2623
IS - 15
ER -