A compound of the formula: or a pharmaceutically acceptable salt or solvate thereof, wherein: X is selected from the group consisting of O and CH 2; R 1 is selected from the group consisting of: -alkylene-S 2 -(C 1 -C 6)alkyl, -alkylene-S 2 -(C 1 -C 6)haloalkyl; -alkylene-S 2 -R 6, -alkylene-S 2 -R 8, -alkylene-S 2 -substituted(C 1 -C 6)alkyl, -alkylene-(tetrahydrothiophene 1,1-dioxide), -alkenyl-S 2 -(C 1 -C 6)alkyl, and -cycloalkyl-S 2 -(C 1 -C 6)alkyl; wherein said -alkylene-S 2 -substituted(C 1 -C 6)alkyl R 1 group is substituted with one or more substituents independently selected from the group consisting of: -OH, halo, -CN, -CF 3, -O-(C 1 -C 6)alkyl, and -O-(halo(C 1 -C 6)alkyl); R 2 is selected from the group consisting of: H and alkyl; R 6 is selected from the group consisting of: unsubstituted (C 6 -C 14)aryl, (C 6 -C 14)aryl substituted with one or more L 1A groups, unsubstituted (C 5 -C 14)heteroaryl, (C 5 -C 14)heteroaryl substituted with one or more L 1A groups, unsubstituted (C 5 -C 14)heteroarylalkyl-, and (C 5 -C 14)heteroarylalkyl- substituted with one or more L 1A groups; R 8 is selected from the group consisting of unsubstituted cycloalkyl and cycloalkyl substituted with one or more L 3 groups (wherein examples of said cycloalkyl groups (unsubstituted or substituted) include C 3 -C 10 cycloalkyl rings); each L 3 is independently selected from the group consisting of: -CN, =O, -CH 2 OH, amino, halo, -CH 2 NH 2, -CH 2 NHalkyl, -C OH, -alkylene-C NH(C 1 to C 6)alkyl, -alkylene-C N((C 1 to C 6)alkyl) 2 wherein each alkyl is independently selected, -alkylene-C NH(C 1 to C 6)haloalkyl, and -alkylene-C N((C 1 to C 6)haloalkyl) 2 wherein each alkyl is independently selected); Ar is selected from the group consisting of: unsubstituted aryl, aryl substituted with one or more L 1A groups, unsubstituted heteroaryl, and substituted heteroaryl substituted with one or more L 1A groups; each L 1 is independently selected from the group consisting of: halogen, alkyl (e.g., C 1 -C 6 alkyl), -CN, -CF 3, -O-(C 1 -C 6)alkyl, -O-(halo(C 1 -C 6)alkyl), -C -O-(C 1 -C 6)alkyl, -alkylene-OH, halo(C 1 -C 6)alkyl, hydroxyalkoxy-, alkoxyalkoxy-, and -S 2 (C 1 -C 6)alkyl; each L 1A is independently selected from the group consisting of: halogen, alkyl, - CN, -CF 3, -O-(C 1 -C 6)alkyl, -O-(halo(C 1 -C 6)alkyl), -C -O-(C 1 -C 6)alkyl, -alkylene-OH, halo(C 1 -C 6)alkyl, hydroxyalkoxy-, alkoxyalkoxy-, and -S 2 (C 1 -C 6)alkyl; and n is 0, 1, 2 or 3; or a compound selected from: and or a pharmaceutically acceptable salt or solvate thereof. X is selected from the group consisting of O and CH 2; R 1 is selected from the group consisting of: -alkylene-S 2 -(C 1 -C 6)alkyl, -alkylene-S 2 -(C 1 -C 6)haloalkyl; -alkylene-S 2 -R 6, -alkylene-S 2 -R 8, -alkylene-S 2 -substituted(C 1 -C 6)alkyl, -alkylene-(tetrahydrothiophene 1,1-dioxide), -alkenyl-S 2 -(C 1 -C 6)alkyl, and -cycloalkyl-S 2 -(C 1 -C 6)alkyl; wherein said -alkylene-S 2 -substituted(C 1 -C 6)alkyl R 1 group is substituted with one or more substituents independently selected from the group consisting of: -OH, halo, -CN, -CF 3, -O-(C 1 -C 6)alkyl, and -O-(halo(C 1 -C 6)alkyl); R 2 is selected from the group consisting of: H and alkyl; R 6 is selected from the group consisting of: unsubstituted (C 6 -C 14)aryl, (C 6 -C 14)aryl substituted with one or more L 1A groups, unsubstituted (C 5 -C 14)heteroaryl, (C 5 -C 14)heteroaryl substituted with one or more L 1A groups, unsubstituted (C 5 -C 14)heteroarylalkyl-, and (C 5 -C 14)heteroarylalkyl- substituted with one or more L 1A groups; R 8 is selected from the group consisting of unsubstituted cycloalkyl and cycloalkyl substituted with one or more L 3 groups (wherein examples of said cycloalkyl groups (unsubstituted or substituted) include C 3 -C 10 cycloalkyl rings); each L 3 is independently selected from the group consisting of: -CN, =O, -CH 2 OH, amino, halo, -CH 2 NH 2, -CH 2 NHalkyl, -C OH, -alkylene-C NH(C 1 to C 6)alkyl, -alkylene-C N((C 1 to C 6)alkyl) 2 wherein each alkyl is independently selected, -alkylene-C NH(C 1 to C 6)haloalkyl, and -alkylene-C N((C 1 to C 6)haloalkyl) 2 wherein each alkyl is independently selected); Ar is selected from the group consisting of: unsubstituted aryl, aryl substituted with one or more L 1A groups, unsubstituted heteroaryl, and substituted heteroaryl substituted with one or more L 1A groups; each L 1 is independently selected from the group consisting of: halogen, alkyl (e.g., C 1 -C 6 alkyl), -CN, -CF 3, -O-(C 1 -C 6)alkyl, -O-(halo(C 1 -C 6)alkyl), -C -O-(C 1 -C 6)alkyl, -alkylene-OH, halo(C 1 -C 6)alkyl, hydroxyalkoxy-, alkoxyalkoxy-, and -S 2 (C 1 -C 6)alkyl; each L 1A is independently selected from the group consisting of: halogen, alkyl, - CN, -CF 3, -O-(C 1 -C 6)alkyl, -O-(halo(C 1 -C 6)alkyl), -C -O-(C 1 -C 6)alkyl, -alkylene-OH, halo(C 1 -C 6)alkyl, hydroxyalkoxy-, alkoxyalkoxy-, and -S 2 (C 1 -C 6)alkyl; and n is 0, 1, 2 or 3;