Heterocyclic Compounds With Oxygen Hetero-atom[s] Only (excl. Compounds Containing Unfused Furan Ring, Whether Or Not Hydrogenated, In The Structure, And Lactones, Isosafrole, 1-[1,3-benzodioxol-5-yl]propan-2-one, Piperonal, Safrole, Tetrahydrocannabinols "all Isomers", And Inorganic Or Organic Compounds Of Mercury)
Heterocyclic Compounds With Oxygen Hetero-atom[s] Only