The synthesis of (S)-¦Â-macrocarpene from (2E,6E)-farnesyl diphosphate proceeds in two steps. The first step is the cyclization to (S)-¦Â-bisabolene. The second step is the isomerization to (S)-¦Â-macrocarpene (cf. EC?5.5.1.17, (S)-¦Â-macrocarpene synthase). The enzyme requires Mg2+?or Mn2+?for activity.