USP30 inhibitors

1. A compound represented by structural formula (I):

or a pharmaceutically acceptable salt thereof, wherein:

X is phenyl or naphthyl;

Y is absent, a methylene group, an ethylene group, or an ethenylene group;

R 1 is (C 1 -C 4 )alkyl, 3-7 membered cycloalkyl, 5-6 membered heterocyclyl, 6-10 membered aryl, or 5-6 membered heteroaryl, each of which is independently optionally substituted with one or more substituents selected from the group consisting of halogen, CN, —CO 2 H, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, methylenedioxy, phenyl, —NO 2 , —OR c , NR a R b , —S(O) i R a , —NR a S(O) i R b , —S(O) i NR a R b , —C(═O)OR a , —OC(═O)OR a , —C(═S)OR a , —O(C═S)R a , —C(═O)NR a R b , —NR a C(═O)R b , —C(═S)NR a R b , —NR a C(═S)R b , —NR a (C═O)OR b , —O(C═O)NR a R b , —NR a (C═S)OR b , —O(C═S)NR a R b , —NR a (C═O)NR a R b , —NR a (C═S)NR a R b , —C(═S)R a , and —C(═O)R a ;

R 2 is 3-7 membered cycloalkyl, 5-6 membered heterocyclyl, 6-10 membered aryl, 5-6 membered heteroaryl, or bridged 5-10 membered cycloalkyl; each of which is independently optionally substituted with one or more substituents selected from the group consisting of halogen, CN, —CO 2 H, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, (C 1 -C 4 )alkylthio, —NO 2 , —NR a R b , —S(O),R a , —NR a S(O) i R b , —S(O) i NR a R b , —C(═O)OR a , —OC(═O)OR a , —C(═S)OR a , —O(C═S)R a , —C(═O)NR a R b , —NR a C(═O)R b , —C(═S)NR a R b , —NR a C(═S)R b , —NR a (C═O)OR b , —O(C═O)NR a R b , —NR a (C═S)OR b , —O(C═S)NR a R b , —NR a (C═O)NR a R b , —NR a (C═S)NR a R b , —C(═S)R a , and —C(═O)R a ;

R 3 is isopropyl, t-butyl, 1-methylcyclopropyl, 1-fluoromethylcyclopropyl, 1-difluoromethylcyclopropyl, 1-trifluoromethylcyclopropyl, or 3-methyl-3-oxetanyl;

each R a and each R b are independently selected from —H and (C 1 -C 5 )alkyl, optionally substituted with hydroxyl or (C 1 -C 3 )alkoxy;

R c is —H, (C 1 -C 5 )haloalkyl or (C 1 -C 5 )alkyl, wherein the (C 1 -C 5 )alkyl is optionally substituted with hydroxyl or (C 1 -C 3 )alkoxy; and

i is 0,1 or 2.

2. The compound of claim 1 , wherein the compound is represented by structural formula (Ia):

or a pharmaceutically acceptable salt thereof.

3. The compound of claim 2 , wherein the compound is represented by structural formula (Ib):

or a pharmaceutically acceptable salt thereof.

4. The compound of claim 2 , wherein the compound is represented by structural formula (Ic):

or a pharmaceutically acceptable salt thereof.

5. The compound of claim 2 , or a pharmaceutically acceptable salt thereof, wherein R 2 is 3-7 membered cycloalkyl optionally substituted with one or more substituents selected from the group consisting of (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkylthio, hydroxyl, halogen, and halo(C 1 -C 4 )alkyl; phenyl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, —CO 2 H, —CO 2 Me, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, and hydroxyl; 5-6 membered heterocyclyl optionally substituted with one or more substituents selected from the group consisting of (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, and (C 1 -C 4 )alkoxy; 5-6 membered heteroaryl optionally substituted with one or more substituents selected from the group consisting of halogen, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, and (C 1 -C 4 )alkoxy; or adamantyl.

6. The compound of claim 5 , or a pharmaceutically acceptable salt thereof, wherein R 1 is (C 1 -C 4 )alkyl optionally substituted with one or more substituents selected from the group consisting of halogen, —CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; 3-7 membered cycloalkyl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; 5-6 membered heterocyclyl optionally substituted with one or more substituents selected from the group consisting of halogen, —CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; phenyl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, methylenedioxy, and phenyl; or 5-6 membered heteroaryl optionally substituted with one or more substituents selected from the group consisting of halogen, —CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio.

7. The compound of claim 2 , or a pharmaceutically acceptable salt thereof, wherein R 2 is 3-7 membered cycloalkyl optionally substituted with one or more substituents selected from the group consisting of halogen and (C 1 -C 4 )alkyl; phenyl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, —CO 2 H, —CO 2 Me, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, and hydroxyl; 5-6 membered heterocyclyl selected from tetrahydrofuranyl or tetrahydro-2H-pyranyl; 5-6 membered heteroaryl optionally substituted with one or more substituents selected from the group consisting of halogen, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, and (C 1 -C 4 )alkoxy, wherein the heteroaryl is pyridyl, pyridazinyl, pyrimidinyl, thiazolyl, oxazolyl, furanyl, pyrrolyl, or thiophenyl.

8. The compound of claim 7 , or a pharmaceutically acceptable salt thereof, wherein R 1 is (C 1 -C 4 )alkyl; 3-7 membered cycloalkyl; tetrahydro-2H-pyranyl; phenyl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and phenyl; 5-6 membered heteroaryl selected from pyridyl, imidazolyl, and thiophenyl.

9. The compound of claim 8 , or a pharmaceutically acceptable salt thereof, wherein R 3 is t-butyl.

10. The compound of claim 2 , or a pharmaceutically acceptable salt thereof, wherein R 1 is (C 1 -C 4 )alkyl optionally substituted with one or more substituents selected from the group consisting of halogen, —CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; a 3-7 membered cycloalkyl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; 5-6 membered heterocyclyl optionally substituted with one or more substituents selected from the group consisting of halogen, —CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; 6-10 membered aryl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, methylenedioxy, and phenyl; 5-6 membered heteroaryl optionally substituted with one or more substituents selected from the group consisting of halogen, —CN, hydroxyl, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, halo(C 1 -C 4 )alkoxy, and (C 1 -C 4 )alkylthio; or a 5-10 membered bicycloalkyl selected from the group consisting of bicyclo[2.2.2]oct-1-yl, bicyclo[2.2.2]oct-2-yl, bicyclo[2.2.1]hept-1-yl, bicyclo[2.2.1]hept-2-yl; bicyclo[1.1.1]pentan-1-yl;

R 2 is a 3-7 membered cycloalkyl optionally substituted with one or more substituents selected from the group consisting of (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkylthio, hydroxyl, halogen, and halo(C 1 -C 4 )alkyl; a 6-10 membered aryl optionally substituted with one or more substituents selected from the group consisting of halogen, CN, —CO 2 H, —CO 2 Me, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, and hydroxyl; a 5-6 membered heterocyclyl optionally substituted with one or more substituents selected from the group consisting of (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy; or a 5-6 membered heteroaryl optionally substituted with one or more substituents selected from the group consisting of halogen, (C 1 -C 4 )alkyl, halo(C 1 -C 4 )alkyl, and (C 1 -C 4 )alkoxy.

11. A pharmaceutical composition comprising a pharmaceutically acceptable carrier or diluent and the compound of claim 1 .

12. A method of treating a ubiquitin specific peptidase 30 (USP30) mediated disorder in a subject comprising administering to the subject an effective amount of the compound of claim 1 .

13. The method of claim 12 , wherein the USP30 mediated disorder involves a mitochondrial defect is selected from the group consisting of a condition involving a mitophagy defect, a condition involving a mutation in mitochondrial DNA, a condition involving mitochondrial oxidative stress, a condition involving a defect in mitochondrial shape or morphology, a condition involving a defect in mitochondrial membrane potential, and a condition involving a lysosomal storage defect.

14. The method of claim 12 , wherein the mitochondrial defect is selected from the group consisting of a neurodegenerative disease; mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome; Leber's hereditary optic neuropathy (LHON); neuropathy, ataxia, retinitis pigmentosa-maternally inherited Leigh syndrome (NARP-MILS); Danon disease; ischemic heart disease leading to myocardial infarction; multiple sulfatase deficiency (MSD); mucolipidosis II (ML II); mucolipidosis III (ML III); mucolipidosis IV (ML IV); GM1-gangliosidosis (GM1); neuronal ceroid-lipofuscinoses (NCL1); Alpers disease; Barth syndrome; Beta-oxidation defects; carnitine-acyl-carnitine deficiency; carnitine deficiency; creatine deficiency syndromes; coenzyme Q10 deficiency; complex I deficiency; complex II deficiency; complex III deficiency; complex IV deficiency; complex V deficiency; COX deficiency; chronic progressive external ophthalmoplegia syndrome (CPEO); CPT I deficiency; CPT II deficiency; glutaric aciduria type II; Kearns-Sayre syndrome; lactic acidosis; long-chain acyl-CoA dehydrongenase deficiency (LCHAD); Leigh disease or syndrome; lethal infantile cardiomyopathy (LIC); Luft disease; glutaric aciduria type II; medium-chain acyl-CoA dehydrongenase deficiency (MCAD); myoclonic epilepsy and ragged-red fiber (MERRF) syndrome; mitochondrial recessive ataxia syndrome; mitochondrial cytopathy; mitochondrial DNA depletion syndrome; myoneurogastointestinal disorder and encephalopathy; Pearson syndrome; pyruvate carboxylase deficiency; pyruvate dehydrogenase deficiency; POLG mutations; medium/short-chain 3-hydroxyacyl-CoA dehydrogenase (M/SCHAD) deficiency; and very long-chain acyl-CoA dehydrongenase (VLCAD) deficiency.

15. The method of claim 14 , wherein the neurodegenerative disease is selected from Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), Huntington's disease, ischemia, stroke, dementia with Lewy bodies, and frontotemporal dementia.

16. The method of claim 15 , wherein the neurodegenerative disease is Parkinson's disease, or amyotrophic lateral sclerosis (ALS).

17. The method of claim 12 , wherein the USP30 mediated disorder is a neoplastic disease selected from metastatic carcinoma, multiple myeloma, osteosarcoma, chondosarcoma, Ewing's sarcoma, nasopharyngeal carcinoma, and leukemia.

18. A method of administering to the subject an effective amount of the compound of claim 1 to promote apoptosis in cells.

19. The method of claim 18 , wherein the cells are cancer cells.

20. The method of claim 19 , wherein the cancer cells are melanoma.