Aza spiro alkane derivatives as inhibitors of metalloproteases

1. A method for treating breast cancer, ovarian cancer, or gastric cancer, in a mammal comprising administering to said mammal in need of such treatment a therapeutically effective amount of a compound according to the following formula:

or an enantiomer, diastereomer, solvate, or pharmaceutically acceptable salt thereof, wherein:

X is CH 2 NR b ;

Y is (CH 2 ) j ;

V is piperidin-1-yl, piperazin-1-yl, pyrrolidin-1-yl, pyridin-1-yl or 3,6-dihydropyridin-1-yl each substituted with 0-5 R e ;

V′ is phenyl substituted with 0-5 R e ;

R b is H, C(O)O(CR b ′R c ′) r -T, or C(O)(CR b ′R c ′) r -T;

R b ′ and R c ′ are both H;

R e is H, C 1-6 alkyl, OH, Cl, F, Br, I, CN, NO 2 , methoxy, ethoxy, n-propoxy, isopropoxy, phenoxy, benzyloxy, amino, (C 1-4 alkyl)amino, (C 2-8 )dialkylamino, C(O)O(C 1-4 alkyl), CONH 2 , CONH(C 1-4 alkyl), CON(C 1-4 alkyl) 2 , C 1-6 haloalkyl, phenyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, benzyl, or phenethyl;

T is H, C 1-10 alkyl substituted with 0 to 5 R b ′; C 2-10 alkenyl substituted with 0 to 5 R b ′, C 2-10 alkynyl substituted with 0 to 5 R b ′, C 3-13 carbocyclyl substituted with 0-3 R b ′, or heterocyclyl substituted with 0-5 R b ′;

j is 1 or 2; and

r is 0, 1 or 2.

2. The method of claim 1 , wherein Y is CH 2 .

3. The method of claim 1 , wherein V′ is phenyl.

4. The method of claim 1 , wherein R b is H.

5. The method of claim 1 , wherein R b is C(O)(CR b ′R c ′) r -T.

6. The method of claim 1 , wherein R b is C(O)O(CR b ′R c ′) r -T.

7. The method of claim 1 , wherein the compound is selected from:

N-hydroxy-6-{[4-(3-methylphenyl)piperazin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenyl-3,6-dihydropyridin-1(2H) -yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Benzyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenyl-3,6-dihydropyridin-1(2H) -yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

6-{[4-[3-(aminocarbonyl)phenyl]-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3-fluoro-2-methylphenyl)piperazin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(2-methyl-3-nitrophenyl)piperazin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[3-methyl-4-(3-methylphenyl)piperazin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(3-methoxyphenyl)piperidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-2-methylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyanophenyl)piperazin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-[(4-phenylpiperidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

N-Hydroxy-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 3-[1-({7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]oct-6-yl}carbonyl)piperidin-4-yl]benzoate;

N-Hydroxy-6-{[4-(3-isopropylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(3-isopropylphenyl)piperidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(4-propylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(4-ethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-Hydroxy-6-{[4-(4-ethylphenyl)piperidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-2-methylphenyl)piperazin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

N-Hydroxy-6-{[4-(3-isopropoxyphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-Hydroxy-6-{[4-(3-methylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-Hydroxy-6-{[4-(3-methylphenyl)piperidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-tert-butylphenyl)piperazin-1-yl]carbonyl}-N -hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(3-isopropoxyphenyl)piperidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 4-[1-({7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]oct-6-yl}carbonyl)- 1 ,2,3 ,6-tetrahydropyridin-4-yl]-3-methylbenzoate;

N-hydroxy-6-{[4-(2-methyl-4-nitrophenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(2-ethylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 4-[1-({7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]oct-6-yl}carbonyl)piperidin-4-yl]-3-methylbenzoate;

N-Hydroxy-6-{[(3R)-3-phenylpyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-Hydroxy-6-{[(3S)-3-phenylpyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-({3-[3-(trifluoromethyl)phenyl]pyrrolidin-1-yl}carbonyl)-5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(3-chlorophenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(3-fluorophenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(4-fluorophenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(4-chlorophenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-({3-[4-(trifluoromethyl)phenyl]pyrrolidin-1-yl}carbonyl)-5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(4-methoxyphenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(4-phenoxyphenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(3-methoxyphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(4-cyano-3-methylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-{[3-(3-methoxyphenyl)pyrrolidin-1-yl]carbonyl}-N-hydroxy -5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(3,5-dimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(5-methoxy-2-methylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[4-(4-methoxy-2-methylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-[(4-cyano-4-phenylpiperidin-1-yl)carbonyl]-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

Ethyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenyl-3,6-dihydropyridin-1(2H)-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Propyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenyl-3,6-dihydropyridin-1(2H) -yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Isopropyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenyl-3,6-dihydropyridin-1(2H) -yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Isobutyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenyl-3,6-dihydropyridin-1(2H) -yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate; and

N-hydroxy-6-[(5-methyl-4-phenyl-3,6-dihydropyridin-1(2H)-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide, or an enantiomer, diastereomer, solvate, or pharmaceutically acceptable salt thereof.

8. The method of claim 1 , wherein the compound is selected from:

6-{[4-(4-fluorophenyl)-3-hydroxypiperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-[(4-methyl-4-phenylpiperidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[(trans)-3-methyl-4-phenylpyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(2-fluorophenyl)piperazin-1-yl]carbonyl}-N-hydroxy-5-azaspiro [2.5]octane-7-carboxamide;

Tetrahydro-2H-pyran-4-yl-7-((hydroxyamino)carbonyl)-6-((4-phenylpiperazin-1-yl)carbonyl)-5-azaspiro(2,5)octane-5-carboxylate;

Ethyl 7-((hydroxyamino)carbonyl)-6((4-phenylpiperazin-1-yl)carbonyl) -5-azaspiro(2,5)octane-5-carboxylate;

Methyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Methyl 7-[(hydroxyamino)carbonyl]-6-{[(3R)-3-phenylpyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-5-carboxylate;

N-hydroxy-6-[(3-methyl-3-phenylpyrrolidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[3-(2-methylphenyl)pyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[3-(4-methylphenyl)pyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

5-acetyl-N-hydroxy-6-[(4-phenyl-3,6-dihydropyridin-1(2H)-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-[(3-phenylpiperidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 6-{[4-(3,5-dimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

6-{[4-(3,5-difluorophenyl)-3,6-dihydropyridin-1(2H) -yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3,5-dichlorophenyl)-3,6-dihydropyridin-1(2H) -yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-[3,5-bis(trifluoromethyl)phenyl]-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N -hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

5-formyl-N-hydroxy-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3,5-difluorophenyl)piperidin-1-yl]carbonyl}-N -hydroxy-5-azaspiro [2.5]octane-7-carboxamide;

6-{[4-(2,5 -dimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(2,4,5-trimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-[(4-biphenyl-3-ylpiperidin-1-yl)carbonyl]-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(2,5-dimethylphenyl)piperidin-1-yl]carbonyl}-N -hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(2,4,5-trimethylphenyl)piperidin-1-yl]carbonyl}-N -hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 3-[1-({7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]oct-6-yl}carbonyl)-1,2,3,6-tetrahydropyridin-4-yl]-4-methylbenzoate;

6-{[4-[3-(dimethylamino)phenyl]-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 3-[1-({7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]oct-6-yl}carbonyl)piperidin-4-yl]-4-methylbenzoate;

6-({4-[3-(dimethylamino)phenyl]piperidin-1-yl}carbonyl)-N -hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(2-methylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-2-methylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-[(3,3-dimethyl-4-phenyl-3,6-dihydropyridin-1(2H) -yl)carbonyl]-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-[(3,3-dimethyl-4-phenylpiperidin-1-yl)carbonyl]-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3-methylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-[3-ethylphenyl]-3,6-dihydropyridin-1(2H) -yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-[3-(ethyloxy)phenyl]-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3-ethylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3-ethoxyphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3-cyclopropylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-methoxy-3,5-dimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N -hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(3,5-dimethyl-4-methoxyphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3-ethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3-ethylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3,5-dimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3,5-dimethylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3-isopropylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyano-3-isopropylphenyl)piperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

Methyl 6-{[4-(4-cyano-2-methylphenyl)piperazin-1-yl]carbonyl}-7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Tetrahydro-2H-pyran-4-yl 6-{[4-(4-cyano-2-methylphenyl)piperazin-1-yl]carbonyl}-7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

N-hydroxy-6-[(3-methyl-4-phenylpiperidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

6-{[5-(aminocarbonyl)-4-phenyl-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyanophenyl)-5-methyl-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

6-{[4-(4-cyanophenyl)-3-methylpiperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[5-methyl-4-(4-nitrophenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

N-hydroxy-6-{[5-methyl-4-(3-nitrophenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

(3S)-tetrahydrofuran-3-yl 7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

(3R)-tetrahydrofuran-3-yl 7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Propyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2,5]octane-5-carboxylate;

Isopropyl 7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Methyl 6-{[4-(3,5-difluorophenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate;

Methyl 6-{[4-(3,5-difluorophenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate; and

N-hydroxy-6-{[4-(4-isopropylphenyl)piperazin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide, or an enantiomer, diastereomer, solvate, or pharmaceutically acceptable salt thereof.

9. The method of claim 1 , wherein the compound is selected from:

(6S ,7S)-N-hydroxy-6-{[4-(3-methylphenyl)piperazin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide, or an enantiomer, diastereomer, solvate, or pharmaceutically acceptable salt thereof.

10. The method of claim 1 , wherein the compound is selected from:

(6S,7S)-6-{[4-(4-fluorophenyl)-3-hydroxypiperidin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

(6S,7S)-N-hydroxy-6-[(4-methyl-4-phenylpiperidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

(6S,7S)-N-hydroxy-6-{[(trans)-3-methyl-4-phenylpyrrolidin -1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

(6S ,7S)-6-{[4-(2-fluorophenyl)piperazin-1-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide;

Tetrahydro-2H-pyran-4-yl-(6S,7S)-7-((hydroxyamino)carbonyl)-6((4-phenylpiperazin-1-yl)carbonyl)-5-azaspiro(2,5)octane-5-carboxylate;

Ethyl (6S,7S)-7-((hydroxyamino)carbonyl)-6-((4-phenylpiperazin -1-yl)carbonyl)-5-azaspiro(2,5)octane-5-carboxylate;

Methyl (6S,7S)-7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate; and

Methyl (6S,7S)-7-[(hydroxyamino)carbonyl]-6-{[(3R)-3-phenylpyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-5-carboxylate, or an enantiomer, diastereomer, solvate, or pharmaceutically acceptable salt thereof.

11. The method of claim 1 , wherein the compound is selected from:

(6S,7S)-N-hydroxy-6-[(3-methyl-3-phenylpyrrolidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

(6S ,7S)-N-hydroxy-6-{[3-(2-methylphenyl)pyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

(6S ,7S)-N-hydroxy-6-{[3-(4-methylphenyl)pyrrolidin-1-yl]carbonyl}-5-azaspiro[2.5]octane-7-carboxamide;

(6S,7S)-5-acetyl-N-hydroxy-6-[(4-phenyl-3,6-dihydropyridin-1(2H)-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

(6S,7S)-N-hydroxy-6-[(3-phenylpiperidin-1-yl)carbonyl]-5-azaspiro[2.5]octane-7-carboxamide;

Methyl (6S,7S)-6-{[4-(3,5-dimethylphenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-7-[(hydroxyamino)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate; and

(6S,7S)-6-{[4-(3,5-difluorophenyl)-3,6-dihydropyridin-1(2H)-yl]carbonyl}-N-hydroxy-5-azaspiro[2.5]octane-7-carboxamide, or an enantiomer, diastereomer, solvate, or pharmaceutically acceptable salt thereof.

12. The method of claim 1 which is a method of treating ovarian cancer.

13. The method of claim 12 wherein the compound is methyl (6S,7S)-7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate, or a pharmaceutically acceptable salt thereof.

14. The method of claim 1 which is a method for treating gastric cancer.

15. The method of claim 14 wherein the compound is methyl (6S,7S)-7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate, or a pharmaceutically acceptable salt thereof.

16. The method of claim 1 which is a method for treating breast cancer wherein the compound is methyl (6S ,7S)-7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate, or a pharmaceutically acceptable salt thereof.

17. The method of claim 1 which is a method for treating breast cancer wherein the compound is methyl (6S ,7S)-7-[(hydroxyamino)carbonyl]-6-[(4-phenylpiperazin-1-yl)carbonyl]-5-azaspiro[2.5]octane-5-carboxylate.