SEARCH Articles Figures Tables Compound labels Compounds hydrogen Compounds isotopes Heterocycles, hydrogenation Hydrogen isotopes Hydrogenated compounds Hydrogenation compounds Hydrogenation labeled Hydrogenous compounds Isotope isotopic labeling Isotope label Isotope-labelled Isotopic hydrogen Isotopic labeling Isotopic labelled Isotopic labelling Isotopic labels Isotopical labeling Isotopically Labelled Heterocycles Isotopically labeled compounds Isotopically labelled compounds Labelled compounds