SEARCH Articles Figures Tables 5-Membered rings heteroatoms Compounds with Heteroatom Five-membered Ring Ligands Five Heteroatoms Five-Membered Ring Systems with Two or More Heteroatoms Five-Membered Rings One Heteroatom Five-Membered Rings with More Than Two Heteroatoms Five-Membered Rings with Two Heteroatoms Five-membered ring Five-membered ring systems heteroatoms Heteroatomic Rings More Than One Heteroatom in the Five-Membered Ring Of heterocycles: five-membered rings with one heteroatom Of heterocycles: five-membered rings with two or more heteroatoms Reactions with Five-Membered Ring Systems Containing One Heteroatom Reactivity of Five-membered Rings with One Heteroatom Reactivity of Five-membered Rings with Two or More Heteroatoms Structure of Five-membered Rings with One Heteroatom Structure of Five-membered Rings with Two or More Heteroatoms Sulfur compounds heteroatoms, five-membered rings Synthesis of Five-Membered Rings with Two Heteroatoms