Selective inhibitor of protein kinase G (Ki values are 0.23, 4 and > 10 μM for inhibition of PKG, PKC and PKA respectively). Inhibits SNP-stimulated PKG activity with an IC50 of 60 nM in dispersed smooth muscle cells and has little effect on PKA activity at concentrations of up to 10 μM. Also available as part of the Mixed Kinase Inhibitor Tocriset™.