Spiro-oxazolones

1. A compound of formula I,

wherein

X 1 , X 2 , X 3 and X 4 are C—R 1 ;

Y is O or S(O) m ;

m is 0, 1 or 2;

R 1 each separately is selected from the group consisting of hydrogen, halogen, hydroxy, C 1-6 -alkyl- and C 1-6 -alkoxy-;

R 2 is selected from the group consisting of H and C 1-6 -alkyl-;

R 3 is selected from the group consisting of H and C 1-6 -alkyl-;

or R 2 and R 3 together are ═O;

R 4 is selected from the group consisting of

i) aryl-C 1-6 -alkyl-, wherein the aryl moiety can be optionally substituted by halogen,

ii) C 1-6 -alkoxy-CH 2 —,

iii) C 1-6 -alkyl-,

iv) C 2-6 -alkenyl-CH 2 —,

v) C 2-6 -alkynyl-CH 2 —,

vi) halogen-C 1-6 -alkyl-,

vii) halogen-C 2-6 -alkenyl-CH 2 —, and

viii) hydrogen;

R 5 is selected from the group consisting of

i) aryl-,

ii) aryl-C 1-6 -alkyl-, wherein

the aryl moiety can be optionally substituted by C 1-6 -alkyl, halogen-C 1-6 -alkyl or halogen, and

the C 1-6 -alkyl moiety can optionally be substituted by C 1-6 -alkyl-COO—, halogen or hydroxy,

iii) C 3-10 -cycloalkyl-C 1-6 -alkyl,

iv) halogen-C 1-6 -alkyl-,

v) heteroaryl-C 1-6 -alkyl-, wherein the heteroaryl moiety can be optionally substituted by halogen,

vi) heterocycloalkyl-C 1-6 -alkyl-,

vii) C 1-6 -alkyl-,

viii) C 2-6 -alkenyl-CH 2 — that is optionally substituted by halogen, (C 1-6 -alkyl) 3 SiO—, C 1-6 -alkyl-COO— or C 1-6 -alkyl-OOC—,

ix) C 1-6 -alkoxy-CH 2 —, and

x) C 2-6 -alkynyl-CH 2 —;

or R 4 and R 5 together are selected from the group consisting of

i) C 3-10 -cycloalkyl that is optionally substituted by C 1-6 -alkyl, C 1-6 -alkoxy, C 1-6 -alkyl-OOC—, halogen, halogen-C 1-6 -alkyl, hydroxy-C 1-6 -alkyl or oxo;

ii) heterocycloalkyl that is optionally substituted by benzyl, C 1-6 -alkyl, C 1-6 -alkyl-OOC—, halogen-C 1-6 -alkyl or oxo;

iii) C 3-10 -cycloalkenyl that is optionally substituted by C 1-6 -alkyl, C 1-6 -alkyl-OOC—, halogen-C 1-6 -alkyl, (C 1-6 -alkyl) 3 SiO—C 1-6 -alkyl- or hydroxy-C 1-6 -alkyl, and

iv) indanyl when Y is SO 2 ;

or pharmaceutically acceptable salts thereof.

2. The compound of claim 1 , wherein

Y is O;

R 4 is selected from the group consisting of

i) aryl-C 1-6 -alkyl-, wherein the aryl moiety can be optionally substituted by halogen,

ii) C 1-6 -alkyl-,

iii) C 2-6 -alkenyl-CH 2 —,

iv) C 2-6 -alkynyl-CH 2 —,

v) halogen-C 2-6 -alkenyl-CH 2 —, and

vi) hydrogen;

R 5 is selected from the group consisting of

i) aryl-,

ii) aryl-C 1-6 -alkyl-, wherein

the aryl moiety can be optionally substituted by C 1-6 -alkyl, halogen-C 1-6 -alkyl or halogen, and

the C 1-6 -alkyl moiety can optionally be substituted by C 1-6 -alkyl-COO—, halogen or hydroxy,

iii) C 3-10 -cycloalkyl-C 1-6 -alkyl-,

iv) heteroaryl-C 1-6 -alkyl-, wherein the heteroaryl moiety can be optionally substituted by halogen,

v) heterocycloalkyl-C 1-6 -alkyl-,

vi) C 1-6 -alkyl-,

vii) C 2-6 -alkenyl-CH 2 — that is optionally substituted by halogen, (C 1-6 -alkyl) 3 SiO—, C 1-6 -alkyl-COO— or C 1-6 -alkyl-OOC—,

viii) C 1-6 -alkoxy-CH 2 —, and

ix) C 2-6 -alkynyl-CH 2 —;

or R 4 and R 5 together are selected from the group consisting of

i) C 3-10 -cycloalkyl that is optionally substituted by C 1-6 -alkyl, C 1-6 -alkoxy, C 1-6 -alkyl-OOC—, C 1-6 -alkyl-COO—, halogen, halogen-C 1-6 -alkyl, hydroxy-C 1-6 -alkyl or oxo;

ii) heterocycloalkyl that is optionally substituted by benzyl, C 1-6 -alkyl, C 1-6 -alkyl-OOC—, halogen-C 1-6 -alkyl or oxo; and

iii) C 3-10 -cycloalkenyl that is optionally substituted by C 1-6 -alkyl, C 1-6 -alkyl-OOC—, halogen-C 1-6 -alkyl, (C 1-6 -alkyl) 3 SiO—C 1-6 -alkyl- or hydroxy-C 1-6 -alkyl.

3. The compound of claim 1 , wherein each R 1 is separately is selected from the group consisting of hydrogen, halogen, and C 1-6 -alkoxy.

4. The compound of claim 1 , wherein R 1 is hydrogen.

5. The compound of claim 1 , wherein Y is O.

6. The compound of claim 1 , wherein Y is SO 2 .

7. The compound of claim 1 , wherein R 2 is hydrogen.

8. The compound of claim 1 , wherein R 3 is hydrogen.

9. The compound of claim 1 , wherein R 2 and R 3 are ═O.

10. The compound of claim 1 , wherein R 4 is hydrogen or C 1-6 -alkyl.

11. The compound of claim 1 , wherein R 5 is benzyl or C 3-10 -cycloalkyl-C 1-6 -alkyl.

12. The compound of claim 1 , wherein R 4 and R 5 together are

i) C 3-10 -cycloalkyl that is optionally substituted by halogen;

ii) heterocycloalkyl that is optionally substituted by C 1-6 -alkyl;

iii) C 3-10 -cycloalkenyl that is optionally substituted by halogen-C 1-6 -alkyl, and

iv) indanyl when Y is SO 2 .

13. The compound of claim 1 , selected from the group consisting of

(−)-(5S)-5-Benzyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-(Cyclopentylmethyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-(Ethoxymethyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(−)-5-[(4-Chlorophenyl)(hydroxy)methyl]-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a,

(+)-5-[(4-Chlorophenyl)(hydroxy)methyl]-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b,

(+)-5-[(5-Chlorothiophen-2-yl)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(−)-5-[(6-Chloropyridin-3-yl)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(−)-5-Benzyl-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(−)-5-Butyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(−)-5-Butyl-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(−)-5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydro-2H-pyran-3-ylmethyl)-1,3-oxazol-4(5H)-one diastereomer a,

(−)-5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydro-2H-pyran-3-ylmethyl)-1,3-oxazol-4(5H)-one diastereomer b,

(+)-5-Methyl-5-(1-phenylethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a,

(+)-5-Methyl-5-(1-phenylethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b,

(+)-(5R)-5-Benzyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-(Cyclopentylmethyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-(Ethoxymethyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-[(4-Chlorophenyl)(hydroxy)methyl]-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a,

(+)-5-[(4-Chlorophenyl)(hydroxy)methyl]-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b,

(+)-5-[(5-Chlorothiophen-2-yl)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-[(6-Chloropyridin-3-yl)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-Benzyl-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-Butyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-Butyl-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

(+)-5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydro-2H-pyran-3-ylmethyl)-1,3-oxazol-4(5H)-one diastereomer a,

(+)-5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydro-2H-pyran-3-ylmethyl)-1,3-oxazol-4(5H)-one diastereomer b,

(+)-5-Methyl-5-(1-phenylethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a,

(+)-5-Methyl-5-(1-phenylethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b,

(4-Chlorophenyl)[4-oxo-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-4,5-dihydro-1,3-oxazol-5-yl]methylacetate,

1′-[5-Benzyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer A,

1′-[5-Benzyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer B,

1′-(4-Oxo-1-oxa-3-azaspiro[4.5]dec-2-en-2-yl)-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-(5-Benzyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl)-4-fluoro-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-(5-Benzyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl)-5-bromo-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-(5-Benzyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl)-5-fluoro-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-(5-Benzyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl)-5-methoxy-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-(5-Butyl-5-methyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl)-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-(8,8-Difluoro-4-oxo-1-oxa-3-azaspiro[4.5]dec-2-en-2-yl)-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-[4-Oxo-8-pentyl-1-oxa-3-azaspiro[4.5]dec-2-en-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one diastereomer a,

1′-[4-Oxo-8-pentyl-1-oxa-3-azaspiro[4.5]dec-2-en-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one diastereomer b,

1′-[5-(4-Chlorobenzyl)-5-methyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer A,

1′-[5-(4-Chlorobenzyl)-5-methyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer B,

1′-[5-(Cyclopentylmethyl)-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer A,

1′-[5-(Cyclopentylmethyl)-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer B,

1′-[5,5-Bis(4-chlorobenzyl)-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

1′-[5-Benzyl-5-methyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer A,

1′-[5-Benzyl-5-methyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer B,

1′-[5-Butyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer A,

1′-[5-Butyl-4-oxo-4,5-dihydro-1,3-oxazol-2-yl]-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one enantiomer B,

1′-{-5-[(4-Chlorophenyl)(hydroxy)methyl]-4-oxo-4, 5-dihydro-1,3-oxazol-2-yl}-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one diastereomer a, enantiomer A,

1′-{-5-[(4-Chlorophenyl)(hydroxy)methyl]-4-oxo-4, 5-dihydro-1,3-oxazol-2-yl}-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one diastereomer a, enantiomer B,

1′-{-5-[(4-Chlorophenyl)(hydroxy)methyl]-4-oxo-4, 5-dihydro-1,3-oxazol-2-yl}-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one diastereomer b, enantiomer A,

1′-{-5-[(4-Chlorophenyl)(hydroxy)methyl]-4-oxo-4, 5-dihydro-1,3-oxazol-2-yl}-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one diastereomer b, enantiomer B,

1′-{5-[(4-Chlorophenyl)(hydroxy)methyl]-5-methyl-4-oxo-4, 5-dihydro-1,3-oxazol-2-yl}-3H-spiro[2-benzofuran-1,4′-piperidin]-3-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,7-dioxa-3-azaspiro[4.5]dec-2-en-4-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]nona-2,7-dien-4-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.5]dec-2-en-4-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-8-thia-3-azaspiro[4.5]dec-2-en-4-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-3a′,4′,6′,6a′-tetrahydro-1′H,4H-spiro[1,3-oxazole-5,2′-pentalene]-4,5′(3′H)-dione,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-3a′,4′-dihydro-1′H,4H-spiro[1,3-oxazole-5,2′-pentalene]-4,5′(3′H)-dione,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-7-(trifluoromethyl)-1-oxa-3-azaspiro[4.4]nona-2,7-dien-4-one,

2′-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3,3a,4,5,6,7,7a-octahydro-4′H-spiro[indene-2,5′-[1,3]oxazol]-4′-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-8-thia-3-azaspiro[4.5]dec-2-en-4-one8,8-dioxide,

2′-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-2,3,4a,5,7,7a-hexahydro-4′H-spiro[cyclopenta[b][1,4]dioxine-6,5′-[1,3]oxazol]-4′-one diastereomer b,

2′-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-3,3a,4,5,6,7,8,8a-octahydro-1H,4′H-spiro[azulene-2,5′-[1,3]oxazol]-4′-one,

2′-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-3a,4,6,6a-tetrahydro-1H,3H,4′H-spiro[cyclopenta[c]furan-5,5′-[1,3]oxazol]-4′-one,

2-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-[2-(trifluoromethyl)prop-2-en-1-yl]-1,3-oxazol-4(5H)-one,

2′-(2,2-Dioxido-1′H,3H-spiro[2-benzothiophene-1,4′-piperidin]-1′-yl)-1,3-dihydro-4′H-spiro[indene-2,5′-[1,3]oxazol]-4′-one,

2-(3H-Spiro[isobenzofuran-1,4′-piperidine]-1′-yl)-1-oxa-3-azaspiro[4.4]non-2-en-4-one,

2-(3H-Spiro[isobenzofuran-1,4′-piperidine]-1′-yl)-5,5-bis(2-(trifluoromethyl)allyl)oxazol-4(5H)-one,

2′-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,2,3,5-tetrahydro-4′H-spiro[2-benzazepine-4,5′-[1,3]oxazol]-4′-one,

2′-(1′H,3H-Spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-3a,4,6,6a-tetrahydro-4′H-spiro[cyclopenta[d][1,3,2]dioxathiole-5,5′-[1,3]oxazol]-4′-one2-oxide,

2-Methyl-2′-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,2,3,5-tetrahydro-4′H-spiro[2-benzazepine-4,5′-[1,3]oxazol]-4′-one,

4-Oxo-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]non-2-ene-7,8-diyldiacetate diastereomer a,

4-Oxo-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]non-2-ene-7,8-diyldiacetate diastereomer b,

5-((4-Chlorophenyl)fluoromethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a, enantiomer A,

5-((4-Chlorophenyl)fluoromethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a, enantiomer B,

5-((4-Chlorophenyl)fluoromethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b, enantiomer A,

5-((4-Chlorophenyl)fluoromethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b, enantiomer B,

5-(2-Bromoprop-2-en-1-yl)-5-(prop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(2-Methylprop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(2-Methylpropyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(4-Chlorobenzyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(4-Chlorobenzyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(But-2-yn-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(Cyclohexylmethyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(Cyclopentylmethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one enantiomer A,

5-(Cyclopentylmethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one enantiomer B,

5-(Cyclopentylmethyl)-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(Hydroxy(phenyl)methyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a, enantiomer A,

5-(Hydroxy(phenyl)methyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a, enantiomer B,

5-(Hydroxy(phenyl)methyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b, enantiomer A,

5-(Hydroxy(phenyl)methyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b, enantiomer B,

5-(Prop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-[2-(trifluoromethyl)prop-2-en-1-yl]-1,3-oxazol-4(5H)-one,

5-(Prop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-(Prop-2-en-1-yl)-5-(prop-2-yn-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5,5-bis(2-Methylprop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5,5-bis(4-Chlorobenzyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5,5-Di(but-2-ynyl)-2-(3H-spiro[isobenzofuran-1,4′-piperidine]-1′-yl)oxazol-4(5H)-one,

5,5-Di(prop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[(4-Chlorophenyl)(fluoro)methyl]-5-methyl-2-(1′H, 3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[(4-Chlorophenyl)(hydroxy)methyl]-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[(4-Chlorophenyl)(hydroxy)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[(5-Chlorothiophen-2-yl)methyl]-5-methyl-2-(1′H, 3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[(6-Chloropyridin-3-yl)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[2-({[tert-Butyl(dimethyl)silyl]oxy}methyl)prop-2-en-1-yl]-5-(prop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-[Hydroxy(phenyl)methyl]-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-{[4-(Difluoromethyl)phenyl](difluoro)methyl}-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5′,5′-Difluoro-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-3′,3a′,4′,5′,6′,6a′-hexahydro-1′H,4H-spiro[1,3-oxazole-5,2′-pentalen]-4-one,

5-Allyl-5-(2-fluoroallyl)-2-(3H-spiro[isobenzofuran-1,4′-piperidine]-1′-yl)oxazol-4(5H)-one,

5-Allyl-5-(2-methylallyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(1′H,3H-spiro[2-benzothiophene-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(1′H,5H-spiro[furo[3,4-b]pyridine-7,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(1′H,7H-spiro[furo[3,4-b]pyridine-5,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(2,2-dioxido-1′H,3H-spiro[2-benzothiophene-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(3,3-dimethyl-1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(3-methyl-1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(4-fluoro-1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(6-fluoro-1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-2-(7-fluoro-1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Benzyl-5-ethyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Butyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Butyl-5-methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydrofuran-3-ylmethyl)-1,3-oxazol-4(5H)-one diastereomer a,

5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydrofuran-3-ylmethyl)-1,3-oxazol-4(5H)-one diastereomer b,

5-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-5-(tetrahydrofuran-2-ylmethyl)-1,3-oxazol-4(5H)-one,

5-Methyl-5-(1-phenylethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer a,

5-Methyl-5-(1-phenylethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one diastereomer b,

5-Methyl-5-(pentafluorobenzyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Methyl-5-(pyrrolidin-1-ylmethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Phenyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

5-Propyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,3-oxazol-4(5H)-one,

7-({[tert-Butyl(dimethyl)silyl]oxy}methyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]nona-2,7-dien-4-one,

7-(Hydroxymethyl)-2-(3H-spiro[isobenzofuran-1,4′-piperidine]-1′-yl)-1-oxa-3-azaspiro[4.4]nona-2,7-dien-4-one,

7,8-Dimethoxy-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]non-2-en-4-one diastereomer a,

7,8-Dimethyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]nona-2,7-dien-4-one,

7-Methyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]nona-2,7-dien-4-one,

8-(2,2-Difluoroethyl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3,8-diazaspiro[4.5]dec-2-en-4-one,

8,8-Difluoro-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.5]dec-2-en-4-one,

8-Benzyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3,8-diazaspiro[4.5]dec-2-en-4-one,

8-Pentyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.5]dec-2-en-4-one diastereomer a,

8-Pentyl-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.5]dec-2-en-4-one diastereomer b,

Ethyl2-((4-oxo-5-(prop-2-ynyl)-2-(3H-spiro[isobenzofuran-1,4′-piperidine]-1′-yl)-4,5-dihydrooxazol-5-yl)methyl)acrylate,

Ethyl2-{[4-oxo-5-(prop-2-en-1-yl)-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-4,5-dihydro-1,3-oxazol-5-yl]methyl}prop-2-enoate,

Ethyl4′-oxo-2′-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-4′H-spiro[bicyclo[3.1.0]hexane-3,5′-[1,3]oxazole]-6-carboxylate diastereomer a,

Ethyl4′-oxo-2′-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-4′H-spiro[bicyclo[3.1.0]hexane-3,5′-[1,3]oxazole]-6-carboxylate diastereomer b,

Ethyl4-oxo-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3-azaspiro[4.4]nona-2,7-diene-7-carboxylate,

tert-Butyl4′-oxo-2′-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1,5-dihydro-4′H-spiro[2-benzazepine-4,5′-[1,3]oxazole]-2(3H)-carboxylate, and

tert-Butyl4-oxo-2-(1′H,3H-spiro[2-benzofuran-1,4′-piperidin]-1′-yl)-1-oxa-3,8-diazaspiro[4.5]dec-2-ene-8-carboxylate,

or pharmaceutically acceptable salts thereof.

14. A pharmaceutical composition comprising a compound of claim 1 together with a pharmaceutically acceptable carrier.