Structural reassignment of compound 968, an allosteric glutaminase inhibitor

• Lindsey A. Albertelli,
• Sainabou Jallow,
• Chun Li and
• Scott M. Ulrich

Beilstein J. Org. Chem. 2026, 22, 455–460, doi:10.3762/bjoc.22.33

• anticancer drug target. Compound 968 is a glutaminase inhibitor that is widely used to probe cancer cells’ dependence on glutaminase activity. Here, we show by NMR spectroscopy and X-ray crystallography that the reported benzo[c]phenanthridine structure of compound 968 is incorrect; its true structure is the

• isomeric benzo[c]acridine. The structural reassignment of compound 968 will aid the medicinal chemistry development of this important compound. Keywords: cancer metabolism; compound 968; glutaminase; Introduction Cancer cells often show a strong reliance on glutamine uptake and metabolism [1][2

• and stabilizes a catalytically inactive form of the enzyme [11][12]. The BPTES scaffold has undergone significant medicinal chemistry development resulting in CB-839/telaglenastat, which is being evaluated in clinical trials in combination with other anticancer agents [13]. Compound 968 is a third