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.
                            本发明涉及一种化合物,其
化学式为(I):其中R1为H或C1-2烷基;R2为H或C1-3烷基;R3和R4分别独立地为H或C1-2烷基,其中烷基可以被选自R10的一到三个相同或不同的取代基所取代;R5为H、羟基、C1-2烷基或OCH3;R10为F或Cl,或其药学上可接受的盐或酯。