Syk

470.45

DMSO 21 mg/mL (44.63 mM)

Powder

R406 is an ATP-competitive inhibitor of Syk with a Ki value of 30 nM. R406 selectively inhibits Syk-dependent signaling with EC50 values ranging from 33 nM to 171 nM, more potently than Syk-independent pathways in different cells. R406 inhibits cellular proliferation of a large panel of diffuse large B-cell lymphoma (DLBCL) cell lines at EC50 values ranging from 0.8 μM to 8.1 μM. R406 treatment (1 μM or 4 μM) induces the activation of caspases 9 and 3, but not caspase 8, leading to significant apoptosis of the majority of DLBCL cell lines. Pretreatment of R406 completely blocks the phosphorylation of SYK525/526 and the SYK-dependent phosphorylation of BLNK in R406-sensitive DLBCLs following B-cell receptor (BCR) crosslinking. R406 potently decreases MMP-9 mRNA levels by 2.8- and 4.3-fold lower than controls after 24 and 48 hours treatment, respectively, and reduces the invasive capacity of the RL cells.

R406 has shown efficacy in a number of animal models of immune disorders. Oral administration of R406 in mice with immune complex-mediated inflammation significantly inhibits the cutaneous reverse passive Arthus reaction by approximately 72% and 86% at 1 mg/kg and 5 mg/kg, respectively, compared with the control. R406 treatment at 10 mg/kg significantly reduces inflammation and swelling, decreases the progressive arthritis to a lower level in the passive anticollagen antibody-challenged mice, and delays the onset and reduces paw thickening and clinical arthritis by approximately 50% in the K/BxN serum transfer mice model.

R406,R-406

C₂₂H₂₃FN₆O₅

841290-80-0