Squalene synthase (EC 2.5. 1.21) catalyses the reductive dimerisation of farnesyl diphosphate in a [1–4] head to head fashion to form squalene, and is the first committed step in cholesterol biosynthesis. Specific inhibitors of squalene synthase would inhibit cholesterol formation and allow production of other important compounds derived from the cholesterol biosynthetic pathway, namely the ubiquinones (co-enzyme Q10), dolichol, and would also ...