A compound of Formula: or a pharmaceutically acceptable salt thereof, wherein: (a) L 1 is O or S; and R 1 is an optionally substituted ring selected from phenyl, an 8-10 membered bicyclic aromatic carbocyclic ring, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or (b) L 1 is a bond; and R 1 is (i) phenyl substituted with 1-4 substituents independently selected from -CN, halogen, -OH, unsubstituted -C 1-6 alkyl, unsubstituted -O-C 1-6 alkyl, and an unsubstituted 3-8 membered monocyclic saturated or partially unsaturated heterocyclic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or (ii) an optionally substituted ring selected from an 8-10 membered bicyclic aromatic carbocyclic ring, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur; L 2 is a C 1-8 bivalent straight or branched hydrocarbon chain, wherein 1, 2, or 3 methylene units of the hydrocarbon chain are optionally and independently replaced with -Cy-, or wherein 1 of the methylene units is optionally and independently replaced with -N -, wherein R is hydrogen; each -Cy- is independently an optionally substituted bivalent ring selected from a 3-6 membered monocyclic, saturated or partially unsaturated, carbocyclic ring, or a 3-6 membered monocyclic, saturated or partially unsaturated, heterocyclic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur; R 2 is -COOR, wherein R is independently selected from hydrogen or optionally substituted -C 1-6 aliphatic; and R 3 is R, halogen, or an optionally substituted ring selected from phenyl, an 8-10 membered bicyclic aromatic carbocyclic ring, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, wherein R is independently selected from hydrogen or optionally substituted -C 1-6 aliphatic. (a) L 1 is O or S; and R 1 is an optionally substituted ring selected from phenyl, an 8-10 membered bicyclic aromatic carbocyclic ring, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur; or (b) L 1 is a bond; and R 1 is (i) phenyl substituted with 1-4 substituents independently selected from -CN, halogen, -OH, unsubstituted -C 1-6 alkyl, unsubstituted -O-C 1-6 alkyl, and an unsubstituted 3-8 membered monocyclic saturated or partially unsaturated heterocyclic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or (ii) an optionally substituted ring selected from an 8-10 membered bicyclic aromatic carbocyclic ring, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur; L 2 is a C 1-8 bivalent straight or branched hydrocarbon chain, wherein 1, 2, or 3 methylene units of the hydrocarbon chain are optionally and independently replaced with -Cy-, or wherein 1 of the methylene units is optionally and independently replaced with -N -, wherein R is hydrogen; each -Cy- is independently an optionally substituted bivalent ring selected from a 3-6 membered monocyclic, saturated or partially unsaturated, carbocyclic ring, or a 3-6 membered monocyclic, saturated or partially unsaturated, heterocyclic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur; R 2 is -COOR, wherein R is independently selected from hydrogen or optionally substituted -C 1-6 aliphatic; and R 3 is R, halogen, or an optionally substituted ring selected from phenyl, an 8-10 membered bicyclic aromatic carbocyclic ring, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, and sulfur, wherein R is independently selected from hydrogen or optionally substituted -C 1-6 aliphatic.