SEARCH Articles Figures Tables 2-Hydroxy five-membered heterocycles, tautomerism Ring-chain tautomerism involving five-membered rings Tautomerism Involving Other Than Five and Six-Membered Tautomerism in Other Five-Membered Ring Lactams Tautomerism of Heterocycles: Five-Membered Rings with Tautomerism of heterocycles: five-membered rings with one Tautomerism of heterocycles: five-membered rings with two