A compound of formula: or a pharmaceutically acceptable salt, ester, or amide thereof, wherein: one of R 1 and R 2 is a group of the formula -L 2 -R 6a -L 3 -R 6b; the other of R 1 and R 2 is selected from the group consisting of hydrogen, alkyl, alkoxy, halogen, cyano, and thioalkoxy; R 3, R 3a, and R 3b are each independently selected from the group consisting of hydrogen, alkyl, trifluoroalkyl, trifluoroalkoxy, alkoxy, halogen, cyano, and thioalkoxy; R 4 and R 5 are each independently selected from the group consisting of alkyl, fluoroalkyl, hydroxyalkyl, alkoxyalkyl, and cycloalkyl, or R 4 and R 5 taken together with the nitrogen atom to which each is attached form a non-aromatic ring of the formula: R 7, R 8, R 9, and R 10 at each occurrence are each independently selected from the group consisting of hydrogen, hydroxyalkyl, fluoroalkyl, cycloalkyl, and alkyl; R 11, R 12, R 13, and R 14 are each independently selected from the group consisting of hydrogen, hydroxyalkyl, alkyl, and fluoroalkyl; R 6a is selected from the group consisting of a 5- to 6-membered heteroaryl ring, cyanophenyl, an 8- to 12-membered bicyclic heteroaryl ring, and a 4- to 12-membered heterocyclic ring; R 6b is selected from the group consisting of hydrogen, a 5- to 6-membered heteroaryl ring, an aryl ring, an 8- to 12-membered bicyclic heteroaryl ring, and a 4- to 12-membered heterocyclic ring; Q is O or S; L is -[C(R 16)(R 17)] k; L 2 is selected from the group consisting of a bond, alkylene, -O-, -C(=O)-, -S-, -NH-, -N(R 16)C(=O)-, -C(=O)N(R 16), and -N(alkyl)-; L 3 is selected from the group consisting of a bond, alkylene, -O-, -C(=O)-, -S-, -N(R 16)C(=O)-, -C(=O)N(R 16), and -N(R 15)-; R 15 is selected from the group consisting of hydrogen, alkyl, acyl, alkoxycarbonyl, amido, and formyl; R 16 and R 17 at each occurrence are independently selected from the group consisting of hydrogen and alkyl; R x and R y at each occurrence are independently selected from the group consisting of hydrogen, hydroxy, hydroxyalkyl, alkyl, alkoxy, alkylamino, fluoro, and dialkylamino; k is 1, 2 or 3; and m is an integer from 1 to 5. one of R 1 and R 2 is a group of the formula -L 2 -R 6a -L 3 -R 6b; the other of R 1 and R 2 is selected from the group consisting of hydrogen, alkyl, alkoxy, halogen, cyano, and thioalkoxy; R 3, R 3a, and R 3b are each independently selected from the group consisting of hydrogen, alkyl, trifluoroalkyl, trifluoroalkoxy, alkoxy, halogen, cyano, and thioalkoxy; R 4 and R 5 are each independently selected from the group consisting of alkyl, fluoroalkyl, hydroxyalkyl, alkoxyalkyl, and cycloalkyl, or R 4 and R 5 taken together with the nitrogen atom to which each is attached form a non-aromatic ring of the formula: R 7, R 8, R 9, and R 10 at each occurrence are each independently selected from the group consisting of hydrogen, hydroxyalkyl, fluoroalkyl, cycloalkyl, and alkyl; R 11, R 12, R 13, and R 14 are each independently selected from the group consisting of hydrogen, hydroxyalkyl, alkyl, and fluoroalkyl; R 6a is selected from the group consisting of a 5- to 6-membered heteroaryl ring, cyanophenyl, an 8- to 12-membered bicyclic heteroaryl ring, and a 4- to 12-membered heterocyclic ring; R 6b is selected from the group consisting of hydrogen, a 5- to 6-membered heteroaryl ring, an aryl ring, an 8- to 12-membered bicyclic heteroaryl ring, and a 4- to 12-membered heterocyclic ring; Q is O or S; L is -[C(R 16)(R 17)] k; L 2 is selected from the group consisting of a bond, alkylene, -O-, -C(=O)-, -S-, -NH-, -N(R 16)C(=O)-, -C(=O)N(R 16), and -N(alkyl)-; L 3 is selected from the group consisting of a bond, alkylene, -O-, -C(=O)-, -S-, -N(R 16)C(=O)-, -C(=O)N(R 16), and -N(R 15)-; R 15 is selected from the group consisting of hydrogen, alkyl, acyl, alkoxycarbonyl, amido, and formyl; R 16 and R 17 at each occurrence are independently selected from the group consisting of hydrogen and alkyl; R x and R y at each occurrence are independently selected from the group consisting of hydrogen, hydroxy, hydroxyalkyl, alkyl, alkoxy, alkylamino, fluoro, and dialkylamino; k is 1, 2 or 3; and m is an integer from 1 to 5.