A compound of formula or a pharmaceutically acceptable salt, solvate or polymorph thereof, wherein R 1 is C 4-8 alkyl substituted with a hydroxyl, R 2 is hydrogen, halogen, hydroxyl, amine, C 1-7 alkyl, C 1-7 alkylamino, C 1-6 alkoxy, (C 1-4)alkoxy-(C 1-4)alkyl, C 3-6 cycloalkyl, C 4-7 heterocycle, aromatic bicyclic heterocycle, arylalkyl, heteroaryl, heteroarylalkyl, carboxylic amide, carboxylic ester each of which is optionally substituted by one or more substituents independently selected from halogen, hydroxyl, amino, C 1-6 alkyl, di-(C 1-6)alkylamino, C 1-6 alkylamino, C 1-6 alkyl, C 1-6 alkoxy, C 3-6 cycloalkyl, carboxylic acid, carboxylic ester, carboxylic amide, heterocycle, aryl, alkenyl, alkynyl, arylalkyl, heteroaryl, heteroarylalkyl or nitrile, R 3 is hydrogen, halogen, hydroxyl, amine, C 1-7 alkyl, C 1-7 alkenyl, C 1-7 alkynyl, C 1-7 alkylamino, C 1-6 alkoxy, (C 1-4)alkoxy-(C 1-4)alkyl, C 3-6 cycloalkyl, C 4-7 heterocycle, aromatic bicyclic heterocycle, arylalkyl, heteroaryl, heteroarylalkyl, aryloxy, heteroaryloxy, ketone, nitrile each of which is optionally substituted by one or more substituents independently selected from halogen, hydroxyl, amino, C 1-6 alkyl, di-(C 1-6)alkylamino, C 1-6 alkylamino, C 1-6 alkyl, C 1-6 alkoxy, C 3-6 cycloalkyl, carboxylic acid, carboxylic ester, carboxylic amide, heterocycle, aryl, alkenyl, alkynyl, arylalkyl, heteroaryl, heteroarylalkyl or nitrile. R 4 is hydrogen, halogen, hydroxyl, amine, C 1-7 alkyl, C 1-7 alkylamino, C 1-6 alkoxy, (C 1-4)alkoxy-(C 1-4)alkyl, C 3-6 cycloalkyl, C 4-7 heterocycle, bicyclic heterocycle, arylalkyl, heteroarylalkyl, aryloxy, heteroaryloxy each of which is optionally substituted by one or more substituents independently selected from halogen, hydroxyl, amino, C 1-6 alkyl, di-(C 1-6)alkylamino, C 1-6 alkylamino, C 1-6 alkyl, C 1-6 alkoxy, C 3-6 cycloalkyl, carboxylic acid, carboxylic ester, carboxylic amide, heterocycle, aryl, alkenyl, alkynyl, arylalkyl, heteroaryl, heteroarylalkyl or nitrile, and R 5 is hydrogen, fluorine, chlorine or methyl with the proviso that R 2, R 3, R 4, and R 5 cannot all be H. R 1 is C 4-8 alkyl substituted with a hydroxyl, R 2 is hydrogen, halogen, hydroxyl, amine, C 1-7 alkyl, C 1-7 alkylamino, C 1-6 alkoxy, (C 1-4)alkoxy-(C 1-4)alkyl, C 3-6 cycloalkyl, C 4-7 heterocycle, aromatic bicyclic heterocycle, arylalkyl, heteroaryl, heteroarylalkyl, carboxylic amide, carboxylic ester each of which is optionally substituted by one or more substituents independently selected from halogen, hydroxyl, amino, C 1-6 alkyl, di-(C 1-6)alkylamino, C 1-6 alkylamino, C 1-6 alkyl, C 1-6 alkoxy, C 3-6 cycloalkyl, carboxylic acid, carboxylic ester, carboxylic amide, heterocycle, aryl, alkenyl, alkynyl, arylalkyl, heteroaryl, heteroarylalkyl or nitrile, R 3 is hydrogen, halogen, hydroxyl, amine, C 1-7 alkyl, C 1-7 alkenyl, C 1-7 alkynyl, C 1-7 alkylamino, C 1-6 alkoxy, (C 1-4)alkoxy-(C 1-4)alkyl, C 3-6 cycloalkyl, C 4-7 heterocycle, aromatic bicyclic heterocycle, arylalkyl, heteroaryl, heteroarylalkyl, aryloxy, heteroaryloxy, ketone, nitrile each of which is optionally substituted by one or more substituents independently selected from halogen, hydroxyl, amino, C 1-6 alkyl, di-(C 1-6)alkylamino, C 1-6 alkylamino, C 1-6 alkyl, C 1-6 alkoxy, C 3-6 cycloalkyl, carboxylic acid, carboxylic ester, carboxylic amide, heterocycle, aryl, alkenyl, alkynyl, arylalkyl, heteroaryl, heteroarylalkyl or nitrile. R 4 is hydrogen, halogen, hydroxyl, amine, C 1-7 alkyl, C 1-7 alkylamino, C 1-6 alkoxy, (C 1-4)alkoxy-(C 1-4)alkyl, C 3-6 cycloalkyl, C 4-7 heterocycle, bicyclic heterocycle, arylalkyl, heteroarylalkyl, aryloxy, heteroaryloxy each of which is optionally substituted by one or more substituents independently selected from halogen, hydroxyl, amino, C 1-6 alkyl, di-(C 1-6)alkylamino, C 1-6 alkylamino, C 1-6 alkyl, C 1-6 alkoxy, C 3-6 cycloalkyl, carboxylic acid, carboxylic ester, carboxylic amide, heterocycle, aryl, alkenyl, alkynyl, arylalkyl, heteroaryl, heteroarylalkyl or nitrile, and R 5 is hydrogen, fluorine, chlorine or methyl with the proviso that R 2, R 3, R 4, and R 5 cannot all be H.