Fluxametamide is a novel isoxazoline insecticide that acts via distinctive antagonism of insect ligand-gated chloride channels, acts as an antagonist of GABA- and glutamate-gated chloride channels(IC50 of 1.95 nM and 225 nM for M. domestica GABACls and GluCls).

GABACls (M. domestica):1.95 nM , GluCls (M. domestica):225 nM

Fluxametamide inhibits GABA responses in the wild-type L. striatellus GABACls with IC50 values of 1.40 (0.57-3.29) nM; in the A2′N mutant GABACls, the IC50 value is 3.51 (2.17-5.69) nM. Moreover, Fluxametamide scarcely inhibits GABA (EC50)-induced currents in rat GABACls at 10 μM and with no inhibition on glycine (EC50)-induced current in human α1 GlyCls at tested concentrations.Fluxametamide is an antagonist of GABA- and glutamate-gated chloride channels, dose-dependently inhibits currents induced by GABA and glutamate in M. domestica GABACls and GluCls, with IC50 values of 1.95 (1.18-3.21) nM and 225 (137-372) nM, respectively, and displays potent antagonistic activity against T. urticae GABACls with an IC50 of 0.219 (0.127-0.381) nM.

Fluxametamide exerts distinctive antagonism of arthropod GABACls by binding to a site different from those for existing antagonists.In contrast to its profound actions on the arthropod LGCCs, the antagonistic activity of fluxametamide against rat GABACls and human glycine-gated chloride channels was nearly insignificant, suggesting that fluxametamide has high target-site selectivity for arthropods over mammals.Overall, fluxametamide is a new type of LGCC antagonist insecticide with excellent safety for mammals at the target-site level.