A compound represented by the following Formula (I) or a pharmaceutically acceptable salt thereof: wherein R 1 represents phenyl optionally substituted with one to three C 1 -C 6 alkyl groups, C 1 -C 6 alkoxy or C 2 -C 6 alkenyloxy； R2 represents a hydrogen atom, C1-C6 alkylcarbonyl or pyridylcarbonyl； R3 and R4 each independently represent a hydrogen atom or C1-C6 alkyl； A represents a single bond, an oxygen atom, a group represented by Formula (II): in which Ra and Rb 10 each independently represent a hydrogen atom or C1-C6 alkyl, and * 1 and * 2 want say binding to carbonyl and R5, respectively, in Formula (I), or a group represented by Formula (III): in which Rc, Rd, Re and Rf each independently represent a hydrogen atom or C1- alkyl C6, and * 1 and * 2 have the same meanings as described above； and R5 represents C1-C6 alkyl or C3-C8 cycloalkyl, and C1-C6 alkyl or C3-C8 cycloalkyl in R5 is optionally substituted with one to three identical or different substituents selected from the group of substituents consisting of an atom of halogen, C1-C6 alkyl and C1-C6 alkoxy.Un compuesto representado por la siguiente Fórmula (I) o una sal farmacéuticamente aceptable del mismo: en la que R1 representa fenilo opcionalmente sustituido con uno a tres grupos alquilo de C1-C6, alcoxi de C1-C6 o alqueniloxi de C2-C6； R2 representa un átomo de hidrógeno, alquilo de C1-C6-carbonilo o piridilcarbonilo； R3 y R4 representan cada uno independientemente un átomo de hidrógeno o alquilo de C1-C6； A representa un enlace sencillo, un átomo de oxígeno, un grupo representado por la Fórmula (II): en la que Ra y Rb 10 representan cada uno independientemente un átomo de hidrógeno o alquilo de C1-C6, y *1 y *2 quieren decir enlazamiento a carbonilo y a R5, respectivamente, en la Fórmula (I), o un grupo representado por la Fórmula (III): en la que Rc, Rd, Re y Rf representan cada uno independientemente un átomo de hidrógeno o alquilo de C1-C6, y *1 y *2 tienen los mismos significados como se des
