1400W is a slow, tight binding, and highly selective inhibitor of inducible nitric-oxide synthase(iNOS).
1400W is either an irreversible inhibitor or an extremely slowly reversible inhibitor of human iNOS. Inhibition of human iNOS by 1400W is time-dependent. 1400W is competitive with L-arginine. 1400W is not a substrate for iNOS.