A compound comprising a structure represented by a formula: wherein each ----- independently comprises an optional covalent bond; wherein R 1 is a C3 to C9 organic residue selected from aryl, heteroaryl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl, and is optionally substituted with one or more groups selected from alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, and thiol; wherein R 2 represents three substituents independently selected from hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, methyl, ethyl, n-propyl, i-propyl, cyclopropyl, n-butyl, i-butyl, s-butyl, cyclobutyl, n-pentyl, i-pentyl, s-pentyl, neopentyl, cyclopentyl, n-hexyl, i-hexyl, s-hexyl, dimethylbutyl, and cyclohexyl; wherein R 3 is hydrogen, C1 to C6 alkyl, C3 to C6 cycloalkyl, or a protecting group; wherein R 4 represents eight substituents independently selected from hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, methyl, ethyl, n-propyl, i-propyl, cyclopropyl, n-butyl, i-butyl, s-butyl, cyclobutyl, n-pentyl, i-pentyl, s-pentyl, neopentyl, cyclopentyl, n-hexyl, i-hexyl, s-hexyl, dimethylbutyl, and cyclohexyl; wherein each of R 5 and R 6 is independently hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, C1 to C6 alkyl, or C3 to C6 cycloalkyl or R 5 and R 6, together with the intermediate carbon, comprise C3 to C6 cycloalkyl; wherein each of R 7 and R 8 is independently hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, C1 to C6 alkyl, or C3 to C6 cycloalkyl or R 7 and R 8, together with the intermediate carbon, comprise C3 to C6 cycloalkyl; wherein R 9 is hydrogen, C1 to C6 alkyl, C3 to C6 cycloalkyl, or a protecting group; wherein R 10 is a C1 to C12 organic residue selected from alkyl, aryl, heteroaryl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl, and is optionally substituted with one or more groups selected from alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, and thiol; wherein R 12 is a covalent bond, a divalent C1 to C3 residue of methyl, ethyl, ethenyl, ethynyl, n-propyl, or i-propyl, or a divalent C1 to C3 residue of cyclopropyl, imidazole, 1,3-dioxolane, or 1,3,5-triazine; and wherein Ar is a C4 to C10 organic residue selected from aryl and heteroaryl, and is optionally substituted with one or more groups selected from alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, and thiol, or a pharmaceutically acceptable salt or N-oxide thereof. wherein each ----- independently comprises an optional covalent bond; wherein R 1 is a C3 to C9 organic residue selected from aryl, heteroaryl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl, and is optionally substituted with one or more groups selected from alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, and thiol; wherein R 2 represents three substituents independently selected from hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, methyl, ethyl, n-propyl, i-propyl, cyclopropyl, n-butyl, i-butyl, s-butyl, cyclobutyl, n-pentyl, i-pentyl, s-pentyl, neopentyl, cyclopentyl, n-hexyl, i-hexyl, s-hexyl, dimethylbutyl, and cyclohexyl; wherein R 3 is hydrogen, C1 to C6 alkyl, C3 to C6 cycloalkyl, or a protecting group; wherein R 4 represents eight substituents independently selected from hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, methyl, ethyl, n-propyl, i-propyl, cyclopropyl, n-butyl, i-butyl, s-butyl, cyclobutyl, n-pentyl, i-pentyl, s-pentyl, neopentyl, cyclopentyl, n-hexyl, i-hexyl, s-hexyl, dimethylbutyl, and cyclohexyl; wherein each of R 5 and R 6 is independently hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, C1 to C6 alkyl, or C3 to C6 cycloalkyl or R 5 and R 6, together with the intermediate carbon, comprise C3 to C6 cycloalkyl; wherein each of R 7 and R 8 is independently hydrogen, halide, hydroxyl, trifluoromethyl, amino, cyano, nitro, azide, carboxamido, alkoxy, thiol, alkylsulfonyl, C1 to C6 alkyl, or C3 to C6 cycloalkyl or R 7 and R 8, together with the intermediate carbon, comprise C3 to C6 cycloalkyl; wherein R 9 is hydrogen, C1 to C6 alkyl, C3 to C6 cycloalkyl, or a protecting group; wherein R 10 is a C1 to C12 organic residue selected from alkyl, aryl, heteroaryl, cycloalkyl, heterocycloalkyl, cycloalkenyl, and heterocycloalkenyl, and is optionally substituted with one or more groups selected from alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, and thiol; wherein R 12 is a covalent bond, a divalent C1 to C3 residue of methyl, ethyl, ethenyl, ethynyl, n-propyl, or i-propyl, or a divalent C1 to C3 residue of cyclopropyl, imidazole, 1,3-dioxolane, or 1,3,5-triazine; and wherein Ar is a C4 to C10 organic residue selected from aryl and heteroaryl, and is optionally substituted with one or more groups selected from alkyl, cycloalkyl, alkoxy, amino, ether, halide, hydroxy, nitro, silyl, sulfo-oxo, and thiol, or a pharmaceutically acceptable salt or N-oxide thereof.