Purity >99% by TLC. Endothelium-derived relaxing factor inhibitor. Inhibits the generation of NO from arginine. Competitive, irreversible non-selective inhibitor of all three NOS I, II, and III isoforms (eNOS, iNOS and nNOS). Inhibits the synthesis of nitric oxide (NO) in a dose-dependent and enantiospecific fashion. Useful tool to study the role and the effects of NO in cardiovascular and gastrointestinal disorders, hypertension, diabetes, septic shock, inflammation, infection, stroke and neurodegenerative disorders.