Fenchol or 1,3,3-trimethyl-2-norbornanol is a monoterpenoid and an isomer of borneol. It is a colorless or white solid. It occurs widely in nature. Fenchol or 1,3,3-trimethyl-2-norbornanol is a monoterpenoid and an isomer of borneol. It is a colorless or white solid. It occurs widely in nature. The naturally occurring enantiopure (1R)-endo-(+)-fenchol is used extensively in perfumery. Fenchol gives basil its characteristic scent, and comprises 15.9% of the volatile oils of some species of Aster. It is biosynthesized from geranyl pyrophosphate via isomerization to linalyl pyrophosphate. Oxidation of fenchol gives fenchone.