5-epi-ñ-Selinene synthase (EC 4.2.3.90, 8a-epi-ñ-selinene synthase, NP1) is an enzyme with systematic name (2Z,6E)-farnesyl-diphosphate diphosphate-lyase (cyclizing, 5-epi-ñ-selinene-forming). This enzyme catalyses the following chemical reaction
This enzyme requires Mg<sup>2+</sup>.