ent-Sandaracopimaradiene is a precursor of the rice oryzalexins A-F. Phytoalexins are diterpenoid secondary metabolites that are involved in the defense mechanism of the plant, and are produced in response to pathogen attack through the perception of elicitor signal molecules such as chitin oligosaccharide, or after exposure to UV irradiation. As a minor product, this enzyme also forms ent-pimara-8(14),15-diene, which is the sole product of EC 4.2.3.30, ent-pimara-8(14),15-diene synthase. ent-Pimara-8(14),15-diene is not a precursor in the biosynthesis of either gibberellins or phytoalexins [2].
