A pharmaceutical composition for inhibiting the autophagy of motor neurons comprising an effective amount of an active ingredient selected from the group consisting of a compound of formula (I), a pharmaceutically acceptable salt of the compound, a pharmaceutically acceptable ester of the compound and combinations thereof: wherein A is a C1-C5 alkyl optionally having one or more unsaturated bonds and being optionally substituted by one or more substituents selected from a group consisting of -OH, =O and C1-C3 alkyl X is H, -OH, Y is O or S and can optionally combine with A to form a five-membered ring and R 1 is H or a substituted or unsubstituted C1-C20 alkyl, wherein one or more -CH 2 - of the C1-C20 alkyl are optionally being replaced by -NH- or -O-.
