Patent ID: 7638505

Claim:
A phosphonic acid compound having the structural formula: wherein: R 1 is selected from the group consisting of hydrogen, C 1-7 alkyl, C 3-10 cycloalkyl, aryl, arylalkyl and heterocyclic, R 2 is selected from the group consisting of hydroxy and hydroxy-protecting groups, and Het is 5- or 6-membered heteroaromatic ring which comprises 1, 2 or 3 heteroatoms independently selected from the group consisting of O, N and S; wherein said heteroaromatic ring is optionally substituted with 1 to 3 substituents independently selected from the group consisting of hydrogen, halogen, hydroxy, C 1-4 alkyl, C 1-4 alkoxy, nitroso, nitro, amino, trifluoromethyl and cyano; and a stereoisomer thereof, a solvate thereof, or a salt thereof.