Patent ID: 6951867

Claim:
A compound of the formula (I): wherein, R 1 represents hydrogen or halogen; R 2 represents hydrogen, 1 to 6 carbon alkyl, aminocarbonyl, or 1 to 6 carbon mono- or di-alkylaminocarbonyl; R 3 represents 1 to 10 carbon alkyl substituted by 1 to 4 substituents independently selected from: hydroxy, oxo, aminocarbonyl, 1 to 6 carbon mono- or di-alkylaminocarbonyl, 1 to 6 carbon alkylsulfonylamino, 3 to 8 carbon cycloalkyl, 6 to 10 carbon aryl which may be substituted by one or more 1 to 6 carbon alkyl groups, or 5 to 10 membered heterocyclic or heterocycliccarbonyl containing 1 to 4 ring heteroatoms; and wherein the compound may be in the form of a free base, a pharmaceutically acceptable salt, solvate, or hydrate.