Purity >95%. Lipoxygenases (LOs) are non-heme iron-containing dioxygenases that catalyze the oxidation of polyunsaturated fatty acids to generate unsaturated fatty acid hydroperoxides. The immediate products of 15-LO fatty acid oxidation act as mediators in inflammation, thrombosis, and cancer. 15-Lipoxygenases (15-LO) inhibitor 1 is a heterocyclic pyrimidobenzothiazine compound that inhibits 15-LO with an IC50 value of 18 μM. The inhibitor appears to act as an antioxidant, interfering with the redox cycle of 15-LO.