L-NIL (N6-(1-Iminoethyl)-lysine, hydrochloride) is a potent and selective inhibitor of nitric oxide synthase that exhibits about 28-fold greater selectivity for inducible nitric oxide synthase (IC50 = 3.3 uM) than for the rat brain constitutive enzyme (IC50 = 92 uM). It exhibits about 10-fold greater inhibitory potency than NG-monomethyl-L-arginine in inhibiting γ-interferon-induced NO2- production (IC50 = 460 nM). White solid soluble in water Store at 4°C C8H18ClN3O2 MW: 223.7 [150403-89-7]