Structure-Enabled Discovery of Novel Macrocyclic Inhibitors Targeting Glutaminase 1 Allosteric Binding Site.
Xu, X., Wang, J., Wang, M., Yuan, X., Li, L., Zhang, C., Huang, H., Jing, T., Wang, C., Tong, C., Zhou, L., Meng, Y., Xu, P., Kou, J., Qiu, Z., Li, Z., Bian, J.(2021) J Med Chem 64: 4588-4611
- PubMed: 33792311 
- DOI: https://doi.org/10.1021/acs.jmedchem.0c02044
- Primary Citation of Related Structures:  
6LOX - PubMed Abstract: 
The inhibition of glutaminase 1 (GLS1) represents a potential treatment of malignant tumors. Structural analysis led to the design of a novel series of macrocyclic GLS1 allosteric inhibitors. Through extensive structure-activity relationship studies, a promising candidate molecule 13b ( LL202 ) was identified with robust GLS1 inhibitory activity (IC 50 = 6 nM) and high GLS1 binding affinity (SPR, K d = 24 nM; ITC, K d = 37 nM). The X-ray crystal structure of the 13b -GLS1 complex was resolved, revealing a unique binding mode and providing a novel structural scaffold for GLS1 allosteric inhibitors. Importantly, 13b clearly adjusted the cellular metabolites and induced an increase in the ROS level by blocking glutamine metabolism. Furthermore, 13b exhibited a similar in vivo antitumor activity as CB839 . This study adds to the growing body of evidence that macrocyclization provides an alternative and complementary approach for the design of small-molecule inhibitors, with the potential to improve the binding affinity to the targets.
Organizational Affiliation: 
Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China.