Tamatinib HCl

Description: Tamatinib HCl (formerly known as R406 HCl) is a novel potent and ATP competitive Syk inhibitor with IC50 of 41 nM in cell-free assays, it strongly inhibits Syk but not Lyn, 5-fold less potent to Flt3. R406 impairs platelet activation and monocyte tissue factor expression triggered by heparin-PF4 complex directed antibodies. R406 blocks fc receptor signaling and reduces immune complex-mediated inflammation. R406 inhibited phosphorylation of Syk substrate linker for activation of T cells in mast cells and B-cell linker protein/SLP65 in B cells. R406 bound to the ATP binding pocket of Syk and inhibited its kinase activity as an ATP-competitive inhibitor (Ki = 30 nM). R406 blocked Syk-dependent FcR-mediated activation of monocytes/macrophages and neutrophils and BCR-mediated activation of B lymphocytes.

References: J Pharmacol Exp Ther. 2006 Dec; 319(3):998-1008; Blood. 2008 Feb 15; 111(4):2230-7.

Related CAS #: 841290-81-1 (besylate) 841290-80-0 (free base)