A compound of Formula I: or an enantiomer or a mixture of enantiomers thereof, or a pharmaceutically acceptable salt, solvate, hydrate, co-crystal, clathrate, or polymorph thereof, wherein: R 1 is optionally substituted monocyclic cycloalkyl, optionally substituted monocyclic aryl, optionally substituted monocyclic heteroaryl or optionally substituted monocyclic heterocyclyl; R 2 and R 3 are each halo; where the substituents on R 1, when present, are one to three groups Q, where each Q is independently alkyl, halo, haloalkyl, oxo, optionally substituted monocyclic cycloalkyl, optionally substituted monocyclic cycloalkylalkyl, optionally substituted monocyclic heterocyclyl, optionally substituted monocyclic heterocyclylalkyl, optionally substituted monocyclic aryl, optionally substituted monocyclic heteroaryl, -R 4 OR 5, -R 4 O-R 4 OR 5, - R 4 N(R 6)(R 7), -R 4 SR 5, - R 4 OR 4 N(R 6)(R 7), -R 4 OR 4 C N(R 6)(R 7), -C R 9 or R 4 S t R 8; where the substituents on Q, when present are one to three groups Q a, where each Q a is independently alkyl, halo, haloalkyl, alkoxyalkyl, oxo, hydroxyl or alkoxy; each R 4 is independently alkylene, alkenylene or a direct bond; each R 5 is independently hydrogen, alkyl, haloalkyl, hydroxyalkyl, alkoxyalkyl, monocyclic cycloalkyl, monocyclic aryl, monocyclic heteroaryl, monocyclic heterocyclyl or monocyclic heterocyclylalkyl, where alkyl, haloalkyl, hydroxyalkyl, alkoxyalkyl, cycloalkyl, aryl, heteroaryl, heterocyclyl or heterocyclylalkyl groups in R 5 are each independently optionally substituted with one to three groups Q 1, where each Q 1 is independently alkyl, haloalkyl or halo; R 6 and R 7 are selected as follows: i) R 6 and R 7 are each independently hydrogen or alkyl; or ii) R 6 and R 7 together with the nitrogen atom on which they are substituted form a 5 or 6-membered heterocyclyl or heteroaryl ring, optionally substituted with one or two halo, alkyl or haloalkyl; R 8 is alkyl, haloalkyl, or hydroxyalkyl; R 9 is alkyl or aryl; J is O or S; and t is 1 or 2. R 1 is optionally substituted monocyclic cycloalkyl, optionally substituted monocyclic aryl, optionally substituted monocyclic heteroaryl or optionally substituted monocyclic heterocyclyl; R 2 and R 3 are each halo; where the substituents on R 1, when present, are one to three groups Q, where each Q is independently alkyl, halo, haloalkyl, oxo, optionally substituted monocyclic cycloalkyl, optionally substituted monocyclic cycloalkylalkyl, optionally substituted monocyclic heterocyclyl, optionally substituted monocyclic heterocyclylalkyl, optionally substituted monocyclic aryl, optionally substituted monocyclic heteroaryl, -R 4 OR 5, -R 4 O-R 4 OR 5, - R 4 N(R 6)(R 7), -R 4 SR 5, - R 4 OR 4 N(R 6)(R 7), -R 4 OR 4 C N(R 6)(R 7), -C R 9 or R 4 S t R 8; where the substituents on Q, when present are one to three groups Q a, where each Q a is independently alkyl, halo, haloalkyl, alkoxyalkyl, oxo, hydroxyl or alkoxy; each R 4 is independently alkylene, alkenylene or a direct bond; each R 5 is independently hydrogen, alkyl, haloalkyl, hydroxyalkyl, alkoxyalkyl, monocyclic cycloalkyl, monocyclic aryl, monocyclic heteroaryl, monocyclic heterocyclyl or monocyclic heterocyclylalkyl, where alkyl, haloalkyl, hydroxyalkyl, alkoxyalkyl, cycloalkyl, aryl, heteroaryl, heterocyclyl or heterocyclylalkyl groups in R 5 are each independently optionally substituted with one to three groups Q 1, where each Q 1 is independently alkyl, haloalkyl or halo; R 6 and R 7 are selected as follows: i) R 6 and R 7 are each independently hydrogen or alkyl; or ii) R 6 and R 7 together with the nitrogen atom on which they are substituted form a 5 or 6-membered heterocyclyl or heteroaryl ring, optionally substituted with one or two halo, alkyl or haloalkyl; i) R 6 and R 7 are each independently hydrogen or alkyl; or ii) R 6 and R 7 together with the nitrogen atom on which they are substituted form a 5 or 6-membered heterocyclyl or heteroaryl ring, optionally substituted with one or two halo, alkyl or haloalkyl; R 8 is alkyl, haloalkyl, or hydroxyalkyl; R 9 is alkyl or aryl; J is O or S; and t is 1 or 2.