Enzyme of the diterpenoid metabolism involved in the biosynthesis of antibacterial oryzalides such as phytocassane. ent-isokaurene + 2 O2 + 2 reduced [NADPH--hemoprotein reductase] = ent-isokaurene-2beta,3beta-diol + 2 H(+) + 2 H2O + 2 oxidized [NADPH--hemoprotein reductase] kcat is 0.01 sec(-1) with ent-isokaurene as substrate. Belongs to the cytochrome P450 family. Truncated N-terminus. Truncated N-terminus.