Discovery of <i>N</i>-Arylsulfonyl-Indole-2-Carboxamide Derivatives as Potent, Selective, and Orally Bioavailable Fructose-1,6-Bisphosphatase Inhibitors—Design, Synthesis, <i>In Vivo</i> Glucose Lowering Effects, and X-ray Crystal Complex Analysis
Jie Zhou, Jianbo Bie, Xiaoyu Wang, Quan Liu, Rongcui Li, Hualong Chen, Jinping Hu, Hui Cao, Wenming Ji, Yan Li, Shuainan Liu, Zhufang Shen, Bailing Xu
Abstract
Liver fructose-1,6-bisphosphatase (FBPase) is a key enzyme in the gluconeogenesis pathway. Inhibiting FBPase activity represents a potential treatment for type 2 diabetes mellitus. A series of novel N-arylsulfonyl-4-arylamino-indole-2-carboxamide derivatives have been disclosed as FBPase inhibitors. Through extensive structure–activity relationship investigations, a promising candidate molecule Cpd118 [sodium (7-chloro-4-((3-methoxyphenyl)amino)-1-methyl-1H-indole-2-carbonyl] [(4-methoxyphenyl)sulfonyl)amide] has been identified with high inhibitory activity against human liver FBPase (IC50, 0.029 ± 0.006 μM) and high selectivity relative to the other six AMP-binding enzymes. Importantly, Cpd118 produced significant glucose-lowering effects on both type 2 diabetic KKAy mice and ZDF rats as demonstrated by substantial reductions in the fasting and postprandial blood glucose levels, as well as the HbA1c level. Furthermore, Cpd118 elicited a favorable pharmacokinetic profile with an oral bioavailability of 99.1%. Moreover, the X-ray crystal structure of the Cpd118–FBPase complex was resolved, which revealed a unique binding mode and provided a structural basis for its high potency and selectivity.