PTP1B-IN-3 diammonium is a highly effective and orally bioavailable inhibitor of the protein tyrosine phosphatase 1B (PTP1B) enzyme, with an IC50 value of 120 nM for both PTP1B and TCPTP, exhibiting potent antidiabetic and anticancer properties, as supported by extensive research [1] [2].

In diet-induced obese (DIO) mice, PTP1B-IN-3 (compounds 3g) exhibits a dose-dependent glucose reduction, showing 60%, 80%, and 100% inhibition at 1, 3, and 10 mg/kg, respectively, with an ED50 of 0.8 mg/kg when administered orally 2 hours before a glucose challenge. PTP1B-IN-3 also delays tumor onset in NDL2 Ptpn1 transgenic mice, increasing the average period before tumor development from 28 to 75 days at 30 mg/kg for 21 days. The compound demonstrates favorable pharmacokinetics in DIO mice, including good oral bioavailability (24%), a slow clearance rate (0.71 mL/kg/min), and a substantial elimination half-life (6 hours). While oral bioavailability is lower in rats (4%) and squirrel monkeys (2%), significant exposure levels are still achieved with oral administration.