abstract |
The present invention relates to a compound of formula (I): wherein: R1 is H or C1-2 alkyl; R2 is H or C1-3 alkyl; R3 and R4 are each independently H or C1-2 alkyl, where the alkyl may be substituted with one to three of the same or different substituents selected from R10; R5 is H, hydroxy, C1-2 alkyl, or OCH3; and R10 is F or Cl, or a pharmaceutically acceptable salt or ester thereof. The formula (I) is shown in the description. |