Prodrugs of alpha-ketoglutarate, alpha-ketobutyrate, alpha-ketoisovalerate, and alpha-ketoisohexanoate, and uses thereof

A compound of formula (VII), or a pharmaceutically acceptable salt thereof:

• wherein:
• R1 is —O(C═O)(alkyl);
• R2 is alkoxy;
• or
• R1 and R2, together with the intervening atoms, form a fused 5-, 6-, or 7-membered heterocycle or cycloalkyl containing 0-3 N atoms and 0-3 O atoms in the ring, wherein the fused 5-, 6-, or 7-membered ring is substituted with halo, —CN, —OH, oxo, alkyl, haloalkyl, alkene, alkyne, alkoxy, heteroalkyl, monocyclic carbocycle, bicyclic carbocycle, monocyclic heterocycle, bicyclic heterocycle, or —CO2(alkyl);
• R3 is alkyl, heteroalkyl, alkoxy, or alkene;
• and
• R4 is alkyl, heteroalkyl, alkoxy, haloalkyl, alkene, or alkyne.