Condensation reaction of carboxylic acid derivatives with hydrazine hydrate yields 3, 5-disubstituted 4-amino-1,2,4-triazoles. This reaction has shown to be sensitive to the presence of bulky substituents in the α-position and the use of poorly reactive carboxylates. In these cases, important amounts of the intermediate hydrazides are isolated. Starting from natural enantiomerically pure α-hydroxy acids such as L-lactic or L-phenyllactic, optically pure synthons based on the 1,2,4-triazole subunit with C₂ symmetry are easily accessible. These heterocyclic subunits can be introduced into macrocyclic frameworks and open-chain analogues to be used as receptors of alkali and alkaline earth or ammonium cations.