The present invention relates to novel phosphonic acid compounds having the structural formula (I): wherein: (a) R is a group of 1 to 5 substituents independently selected from the group consisting of fluoro, chloro, bromo, C alkoxy, C alkyl, hydroxy, formyl, trifluoromethoxy, phenyl, heterocyclic, heterocyclic-substituted methyl, aminomethyl, hydroxy methyl, bromomethyl, sulfonyl chloride, acetyl chloride, nitroso and cyano, (b) R is selected from the group consisting of hydrogen, C alkyl, C cycloalkyl, aryl, arylalkyl and heterocyclic, and (c) R is selected from the group consisting of hydroxy and hydroxy-protecting groups, and stereoisomer, solvates and salts thereof. These compounds are useful as anti-infectious and anti-parasitic agents, in particular anti-malaria agents.
