Compounds that expand hematopoietic stem cells

1. A compound of Formula Ia:

in which:

L is selected from —NR 5a (CH 2 ) 2-3 , —NR 5a (CH 2 ) 2 NR 5b —, —NR 5a (CH 2 ) 2 S—, —NR 5a CH 2 CH(OH)— and —NR 5a CH(CH 3 )CH 2 —; wherein R 5a and R 5b are independently selected from hydrogen and C 1-4 alkyl;

R 1 is selected from thiophenyl, 1H-benzoimidazolyl, isoquinolinyl, 1H-imidazopyridinyl, benzothiophenyl, pyrimidinyl, pyridinyl, pyrazinyl, pyridazinyl, and thiazolyl; wherein

said thiophenyl, 1H-benzoimidazolyl, isoquinolinyl, 1H-imidazopyridinyl, benzothiophenyl, pyrimidinyl, pyridinyl, pyrazinyl, pyridazinyl, or thiazolyl of R 1 can be optionally substituted by 1 to 3 radicals independently selected from cyano, hydroxy, C 1-4 alkyl, C 1-4 alkoxy, halo, halo-substituted-C 1-4 alkyl, halo-substituted-C 1-4 alkoxy, amino, —C(O)R 8a , —S(O) 0-2 R 8a , —C(O)OR 8a and —C(O)NR 8a R 8b ; wherein R 8a and R 8b are independently selected from hydrogen and C 1-4 alkyl;

R 2 is selected from —S(O) 2 NR 6a R 6b , —NR 6a C(O)R 6b —, —NR 6a C(O)NR 6b R 6c , phenyl, 1H-pyrrolopyridin-3-yl, 1H-pyrrolopyridin-5-yl, 1H-indolyl thiophenyl, pyridinyl, 1H-1,2,4-triazolyl, 2-oxoimidazolidinyl, 1H-pyrazolyl, 2-oxo-2,3-dihydro-1H-benzoimidazolyl and 1H-indazolyl; wherein

R 6a , R 6b and R 6c are independently selected from hydrogen and C 1-4 alkyl; and

said phenyl, 1H-pyrrolopyridin-3-yl, 1H-pyrrolo[2,3-b]pyridin-5-yl, 1H-indolyl, thiophenyl, pyridinyl, 1H-1,2,4-triazolyl, 2-oxoimidazolidinyl, 1H-pyrazolyl, 2-oxo-2,3-dihydro-1H-benzoimidazolyl or 1H-indazolyl of R 2 is optionally substituted with 1 to 3 radicals independently selected from hydroxy, halo, methyl, methoxy, amino, —O(CH 2 ) 2 NR 7a R 7b , —S(O) 2 NR 7a R 7b , —OS(O) 2 NR 7a R 7b and —NR 7a S(O) 2 R 7b ; wherein R 7a and R 7b are independently selected from hydrogen and C 1-4 alkyl;

R 3 is selected from hydrogen, C 1-4 alkyl and biphenyl; and

R 4 is selected from C 1-10 alkyl, prop-1-en-2-yl, cyclohexyl, cyclopropyl, 2-(2-oxopyrrolidin-1-yl)ethyl, oxetan-2-yl, oxetan-3-yl, benzhydryl, tetrahydro-2H-pyran-2-yl, tetrahydro-2H-pyran-3-yl, phenyl, tetrahydrofuran-3-yl, and benzyl, (4-pentylphenyl)(phenyl)methyl and 1-(1-(2-oxo-6,9,12-trioxa-3-azatetradecan-14-yl)-1H-1,2,3-triazol-4-yl)ethyl wherein

said alkyl, cyclopropyl, cyclohexyl, 2-(2-oxopyrrolidin-1-yl)ethyl, oxetan-3-yl, oxetan-2-yl, benzhydryl, tetrahydro-2H-pyran-2-yl, tetrahydro-2H-pyran-3-yl, phenyl, tetrahydrofuran-3-yl, benzyl, (4-pentylphenyl)(phenyl)methyl or 1-(1-(2-oxo-6,9,12-trioxa-3-azatetradecan-14-yl)-1H-1,2,3-triazol-4-yl)ethyl can be optionally substituted with 1 to 3 radicals independently selected from hydroxy, C 1-4 alkyl and halo-substituted-C 1-4 alkyl;

or a salt thereof.

2. The compound of claim 1 :

R 1 is selected from thiophen-2-yl, thiophen-3-yl, 1H-benzo[d]imidazol-1-yl, isoquinolin-4-yl, 1H-imidazo[4,5-b]pyridin-1-yl, benzo[b]thiophen-3-yl, pyrimidin-5-yl, pyridin-2-yl, pyridin-4-yl, pyrazin-2-yl, pyridin-3-yl, pyridazin-4-yl and thiazol-5-yl; wherein

said thiophen-2-yl, thiophen-3-yl, 1H-benzo[d]imidazol-1-yl, isoquinolin-4-yl, 1H-imidazo[4,5-b]pyridin-1-yl, benzo[b]thiophen-3-yl, pyrimidin-5-yl, pyridiny-2-yl, pyridin-4-yl, pyrazin-2-yl, pyridiny-3-yl, pyridazin-4-yl or thiazol-5-yl of R 1 can be optionally substituted by 1 to 3 radicals independently selected from cyano, hydroxy, C 1-4 alkyl, C 1-4 alkoxy, halo, halo-substituted-C 1-4 alkyl, —S(O) 0-2 R 8a and —C(O)OR 8a ; wherein R 8a is selected from hydrogen and C 1-4 alkyl;

R 2 is selected from —NR 6a C(O)NR 6b R 6c , phenyl, 1H-pyrrolo[2,3-b]pyridin-3-yl, 1H-pyrrolo[2,3-b]pyridin-5-yl, 1H-indol-3-yl, thiophen-3-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, 1H-1,2,4-triazol-3-yl, 1H-1,2,4-triazol-5-yl, 2-oxoimidazolidin-1-yl, 1H-pyrazol-3-yl, 1H-pyrazol-4-yl, 2-oxo-2,3-dihydro-1H-benzo[d]imidazol-5-yl, and 1H-indazol-3-yl; wherein

R 6a , R 6b and R 6c are independently selected from hydrogen and C 1-4 alkyl;

said phenyl, 1H-pyrrolo[2,3-b]pyridin-3-yl, 1H-pyrrolo[2,3-b]pyridin-5-yl, 1H-indol-3-yl, thiophen-3-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, 1H-1,2,4-triazol-3-yl, 1H-1,2,4-triazol-5-yl, 2-oxoimidazolidin-1-yl, 1H-pyrazol-3-yl, 1H-pyrazol-4-yl, 2-oxo-2,3-dihydro-1H-benzo[d]imidazol-5-yl or 1H-indazol-3-yl of R 2 is optionally substituted with 1 to 3 radicals independently selected from hydroxy, halo, methoxy, amino, —OS(O) 2 NR 7a R 7b and —NR 7a S(O) 2 R 7b ; wherein R 7a and R 7b are independently selected from hydrogen and C 1-4 alkyl; and

R 4 is selected from isopropyl, methyl, ethyl, prop-1-en-2-yl, isobutyl, cyclohexyl, sec-butyl, (S)-sec-butyl, (R)-sec-butyl, 1-hydroxypropan-2-yl, (S)-1-hydroxypropan-2-yl, (R)-1-hydroxypropan-2-yl, nonan-2-yl, 2-(2-oxopyrrolidin-1-yl)ethyl, oxetan-3-yl, oxetan-2-yl, benzhydryl, tetrahydro-2H-pyran-2-yl, phenyl, tetrahydrofuran-3-yl and benzyl; wherein

said cyclohexyl, 2-(2-oxopyrrolidin-1-yl)ethyl, oxetan-3-yl, oxetan-2-yl, benzhydryl, tetrahydro-2H-pyran-2-yl, phenyl, tetrahydrofuran-3-yl or benzyl can be optionally substituted with 1 to 3 radicals independently selected from C 1-4 alkyl and halo-substituted-C 1-4 alkyl.

3. The compounds of claim 2 in which L is selected from —NH(CH 2 ) 2-3 —, —NH(CH 2 ) 2 NH—, —NH(CH 2 ) 2 S—, —NHCH(CH 3 )CH 2 — and —NHCH 2 CH(OH)—.

4. The compounds of claim 3 , in which L is —NH(CH 2 ) 2 —.

5. The compound of claim 4 , in which R 2 is selected from phenyl, 1H-indol-3-yl, thiophen-3-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, 1H-1,2,4-triazol-3-yl, 1H-1,2,4-triazol-5-yl, 2-oxoimidazolidin-1-yl, 1H-pyrazol-3-yl, 1H-pyrazol-4-yl, and 2-oxo-2,3-dihydro-1H-benzo[d]imidazol-5-yl; wherein

said phenyl, 1H-indol-3-yl, thiophen-3-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, 1H-1,2,4-triazol-3-yl, 1H-1,2,4-triazol-5-yl, 2-oxoimidazolidin-1-yl, 1H-pyrazol-3-yl, 1H-pyrazol-4-yl, or 2-oxo-2,3-dihydro-1H-benzo[d]imidazol-5-yl of R 2 is optionally substituted with hydroxy, methoxy, methyl, halo, amino and amino-sulfonyl.

6. The compound of claim 5 , in which

R 4 is selected from isopropyl, methyl, ethyl, prop-1-en-2-yl, isobutyl, cyclohexyl, sec-butyl, (S)-sec-butyl, (R)-sec-butyl, 1-hydroxypropan-2-yl, (S)-1-hydroxypropan-2-yl, (R)-1-hydroxypropan-2-yl, nonan-2-yl.

7. The compound of claim 1 selected from:

4-(2-(2-(benzo[b]thiophen-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-sec-butyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-benzhydryl-2-(benzo[b]thiophen-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-(tetrahydro-2H-pyran-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(thiophen-2-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-(4-(trifluoromethyl)benzyl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-isobutyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-methyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-(4-methylbenzyl)-9H-purin-6-ylamino)ethyl)phenol;

N-(2-(1H-indol-3-yl)ethyl)-2-(benzo[b]thiophen-3-yl)-9-isopropyl-9H-purin-6-amine;

2-(benzo[b]thiophen-3-yl)-9-isopropyl-N-(2-(thiophen-3-yl)ethyl)-9H-purin-6-amine;

3-(2-(2-(benzo[b]thiophen-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

2-(benzo[b]thiophen-3-yl)-N-(4-fluorophenethyl)-9-isopropyl-9H-purin-6-amine;

N-(4-aminophenethyl)-2-(benzo[b]thiophen-3-yl)-9-isopropyl-9H-purin-6-amine;

4-(2-(9-isopropyl-2-(pyrimidin-5-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(thiophen-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

2-(benzo[b]thiophen-3-yl)-N-(4-fluorophenethyl)-9-phenyl-9H-purin-6-amine;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-(nonan-2-yl)-9H-purin-6-ylamino)ethyl)phenol;

N-(2-(1H-indol-3-yl)ethyl)-2-(benzo[b]thiophen-3-yl)-9-sec-butyl-9H-purin-6-amine;

4-(2-(9-isopropyl-2-(pyridin-4-yl)-9H-purin-6-ylamino)ethyl)phenol;

ethyl 5-(6-(4-hydroxyphenethylamino)-9-isopropyl-9H-purin-2-yl)nicotinate;

4-(2-((9-isopropyl-2-(5-methoxypyridin-3-yl)-9H-purin-6-yl)amino)ethyl)phenol;

4-(2-(2-(6-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(4-methylpyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

5-(6-(4-hydroxyphenethylamino)-9-isopropyl-9H-purin-2-yl)nicotinonitrile;

4-(2-(9-isopropyl-2-(pyridazin-4-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyrazin-2-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyridin-2-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(5-(methylsulfonyl)pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(5-methylpyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(4-chloropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-((9-isopropyl-2-(4-methylthiophen-3-yl)-9H-purin-6-yl)amino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)-2-methoxyphenol;

N-[2-(6-methoxy-1H-indol-3-yl)ethyl]-9-(propan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-amine;

N-[2-(5-methyl-1H-indol-3-yl)ethyl]-9-(propan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-amine;

1-(2-{[9-(propan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-yl]amino}ethyl)imidazolidin-2-one;

N-(2-{[9-(propan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-yl]amino}ethyl)pyridin-2-amine;

9-(propan-2-yl)-N-[3-(1H-pyrazol-4-yl)propyl]-2-(pyridin-3-yl)-9H-purin-6-amine;

N-{2-[(3-methyl-1H-1,2,4-triazol-5-yl)sulfanyl]ethyl}-9-(propan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-amine;

1-(2-{[2-(1-benzothiophen-3-yl)-9-(propan-2-yl)-9H-purin-6-yl]amino}ethyl)imidazolidin-2-one;

N-[2-(5-amino-1H-1,2,4-triazol-3-yl)ethyl]-2-(1-benzothiophen-3-yl)-9-(propan-2-yl)-9H-purin-6-amine;

N-(2-{[2-(1-benzothiophen-3-yl)-9-(propan-2-yl)-9H-purin-6-yl]amino}ethyl)pyridin-2-amine;

2-(1-benzothiophen-3-yl)-9-(propan-2-yl)-N-[3-(1H-pyrazol-4-yl)propyl]-9H-purin-6-amine;

2-(1-benzothiophen-3-yl)-N-[3-(3,5-dimethyl-1H-pyrazol-4-yl)propyl]-9-(propan-2-yl)-9H-purin-6-amine;

(2-{[2-(1-benzothiophen-3-yl)-9-(propan-2-yl)-9H-purin-6-yl]amino}ethyl)urea;

N-[2-(1H-indol-3-yl)ethyl]-9-(propan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-amine;

N-(4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenyl)methane-sulfonamide;

4-(2-(2-(pyridin-3-yl)-9-(tetrahydrofuran-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)propyl)phenol;

4-(2-(9-(oxetan-3-yl)-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-((9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-yl)(methyl)amino)ethyl)phenol;

4-(2-(9-(1-hydroxypropan-2-yl)-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenyl sulfamate;

4-(2-(2-(2-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(thiazol-5-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(1H-benzo[d]imidazol-1-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

5-(9-sec-butyl-6-(4-hydroxy-3-methylphenethylamino)-9H-purin-2-yl)nicotinonitrile;

N-(2-(1H-pyrrolo[2,3-b]pyridin-5-yl)ethyl)-9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-amine;

9-isopropyl-N-(2-(5-methyl-1H-pyrazol-3-yl)ethyl)-2-(pyridin-3-yl)-9H-purin-6-amine;

4-(2-(2-(5-fluoropyridin-3-yl)-9-(oxetan-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(2-(5-chloropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(5-(trifluoromethyl)pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

5-(6-(2-(1H-indol-3-yl)ethylamino)-9-sec-butyl-9H-purin-2-yl)nicotinonitrile;

N-(2-(1H-indol-3-yl)ethyl)-9-sec-butyl-2-(5-methylpyridin-3-yl)-9H-purin-6-amine;

(R)—N-(2-(1H-indol-3-yl)ethyl)-9-sec-butyl-2-(5-fluoropyridin-3-yl)-9H-purin-6-amine;

(S)—N-(2-(1H-indol-3-yl)ethyl)-9-sec-butyl-2-(5-fluoropyridin-3-yl)-9H-purin-6-amine;

N-(2-(1H-indol-3-yl)ethyl)-9-sec-butyl-2-(5-fluoropyridin-3-yl)-9H-purin-6-amine;

(R)—N-(2-(1H-indol-3-yl)ethyl)-9-sec-butyl-2-(5-methylpyridin-3-yl)-9H-purin-6-amine;

(S)—N-(2-(1H-indol-3-yl)ethyl)-9-sec-butyl-2-(5-methylpyridin-3-yl)-9H-purin-6-amine;

5-(6-(4-hydroxyphenethylamino)-9-(oxetan-3-yl)-9H-purin-2-yl)nicotinonitrile;

(R)-4-(2-(2-(5-fluoropyridin-3-yl)-9-(tetrahydrofuran-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)-3-methylphenol;

5-(6-(4-hydroxyphenethylamino)-9-isopropyl-9H-purin-2-yl)picolinonitrile;

3-(6-(4-hydroxyphenethylamino)-9-isopropyl-9H-purin-2-yl)isonicotinonitrile;

3-(6-(4-hydroxyphenethylamino)-9-isopropyl-9H-purin-2-yl)picolinonitrile;

4-(2-(9-isopropyl-2-(6-methylpyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(isoquinolin-4-yl)-9H-purin-6-ylamino)ethyl)phenol;

2-chloro-4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

3-fluoro-4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

N-(2-(5-chloro-1H-indol-3-yl)ethyl)-9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-amine;

N-(2-(5-fluoro-1H-indol-3-yl)ethyl)-9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-amine;

4-(2-(9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-ylamino)ethyl)-2-methylphenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-(oxetan-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

(S)-4-(2-(2-(benzo[b]thiophen-3-yl)-9-(tetrahydrofuran-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

(R)-4-(2-(2-(benzo[b]thiophen-3-yl)-9-(tetrahydrofuran-3-yl)-9H-purin-6-ylamino)ethyl)phenol;

2-(6-(2-(1H-indol-3-yl)ethylamino)-2-(5-fluoropyridin-3-yl)-9H-purin-9-yl)propan-1-ol;

(R)-2-(6-(2-(1H-indol-3-yl)ethylamino)-2-(5-fluoropyridin-3-yl)-9H-purin-9-yl)propan-1-ol;

(S)-2-(6-(2-(1H-indol-3-yl)ethylamino)-2-(5-fluoropyridin-3-yl)-9H-purin-9-yl)propan-1-ol;

(R)—N-(2-(1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-(tetrahydrofuran-3-yl)-9H-purin-6-amine;

4-(2-(2-(1H-imidazo[4,5-b]pyridin-1-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)phenol;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(pyridin-3-yl)ethyl)-9H-purin-6-amine;

4-(2-(2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)-1-hydroxyethyl)phenol;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(6-methoxy-1H-indol-3-yl)ethyl)-9H-purin-6-amine;

N-(2-(1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-amine;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-9H-purin-6-amine;

N-(2-(1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-(prop-1-en-2-yl)-9H-purin-6-amine;

5-(2-(2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)pyridin-2-ol;

N-(2-(1H-pyrrolo[2,3-b]pyridin-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-amine;

N-(2-(6-(2-(diethylamino)ethoxy)-1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-amine;

3-(2-(2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-ylamino)ethyl)-1H-indol-6-ol;

N-(2-(1H-indol-3-yl)ethyl)-9-isopropyl-2-(5-methylpyridin-3-yl)-9H-purin-6-amine;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(7-methyl-1H-indol-3-yl)ethyl)-9H-purin-6-amine;

N-(2-(1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-(oxetan-3-yl)-9H-purin-6-amine;

N-(2-(1H-indol-3-yl)ethyl)-2-(5-methylpyridin-3-yl)-9-(oxetan-3-yl)-9H-purin-6-amine;

N-(2-(6-fluoro-1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-amine;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(6-methyl-1H-indol-3-yl)ethyl)-9H-purin-6-amine;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(2-methyl-1H-indol-3-yl)ethyl)-9H-purin-6-amine;

N-(2-(4-fluoro-1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-amine;

N-(2-(7-fluoro-1H-indol-3-yl)ethyl)-2-(5-fluoropyridin-3-yl)-9-isopropyl-9H-purin-6-amine;

2-(5-fluoropyridin-3-yl)-9-isopropyl-N-(2-(4-methyl-1H-indol-3-yl)ethyl)-9H-purin-6-amine;

N-(2-(1H-pyrrolo[2,3-b]pyridin-5-yl)ethyl)-9-isopropyl-2-(pyridin-3-yl)-9H-purin-6-amine;

4-(2-(2-(5-fluoropyridin-3-yl)-9-(1-hydroxypropan-2-yl)-9H-purin-6-ylamino)ethyl)-2-methylphenol;

4-(2-(2-(benzo[b]thiophen-3-yl)-9-cyclohexyl-9H-purin-6-ylamino)ethyl)phenol;

4-(2-(9-isopropyl-2-(thiophen-3-yl)-9H-purin-6-ylamino)ethyl)phenol; and

1-(2-(2-(benzo[b]thiophen-3-yl)-6-(4-hydroxyphenethylamino)-9H-purin-9-yl)ethyl)pyrrolidin-2-one;

or a salt thereof.

8. The compound of claim 1 , wherein the compound is of formula 1a:

in which

L is —NH(CH 2 ) 2 —;

R 1 is selected from thiophen-2-yl, thiophen-3-yl, benzo[b]thiophen-3-yl, pyrimidin-5-yl, pyridin-2-yl, pyridin-4-yl, pyrazin-2-yl, pyridin-3-yl, pyridazin-4-yl, and thiazol-5-yl; wherein

said thiophen-2-yl, thiophen-3-yl, benzo[b]thiophen-3-yl, pyrimidin-5-yl, pyridin-2-yl, pyridin-4-yl, pyrazin-2-yl, pyridin-3-yl, pyridazin-4-yl, and thiazol-5-yl of R 1 can be optionally substituted by 1 to 3 radicals independently selected from cyano, hydroxy, C 1-4 alkyl, C 1-4 alkoxy, halo, halo-substituted-C 1-4 alkyl, —S(O) 0-2 R 8a and —C(O)OR 8a ; wherein R 8a is selected from hydrogen and C 1-4 alkyl;

R 2 is selected from phenyl, 1H-indol-3-yl, thiophen-3-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, 1H-1,2,4-triazol-5-yl, 2-oxoimidazolidin-1-yl, 1H-pyrazol-3-yl, 1H-pyrazol-4-yl, 2-oxo-2,3-dihydro-1H-benzo[d]imidazol-5-yl; wherein

said phenyl, 1H-indol-3-yl, thiophen-3-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, 1H-1,2,4-triazol-5-yl, 2-oxoimidazolidin-1-yl, 1H-pyrazol-3-yl, 1H-pyrazol-4-yl, 2-oxo-2,3-dihydro-1H-benzo[d]imidazol-5-yl of R 2 is optionally substituted with 1 to 3 radicals independently selected from hydroxy, halo, methoxy, amino, —OS(O) 2 NR 7a R 7b and —NR 7a S(O) 2 R 7b ; wherein R 7a and R 7b are independently selected from hydrogen and C 1-4 alkyl;

R 3 is hydrogen, C 1-4 alkyl and biphenyl; and

R 4 is selected from isopropyl, isobutyl, sec-butyl, 1-hydroxypropan-2-yl, oxetan-3-yl, oxetan-2-yl, benzhydryl, tetrahydro-2H-pyran-2-yl, phenyl, tetrahydrofuran-3-yl and benzyl; wherein

said oxetan-3-yl, oxetan-2-yl, benzhydryl, tetrahydro-2H-pyran-2-yl, phenyl, tetrahydrofuran-3-yl or benzyl can be optionally substituted with 1 to 3 radicals independently selected from C 1-4 alkyl and halo-substituted-C 1-4 alkyl.

9. The compound of claim 1 , wherein the compound is of formula 1f:

in which:

R 2 is selected from 1H-indol-3-yl and phenyl optionally substituted with hydroxy; and

R 4 is selected from isopropyl, sec-butyl, benzhydryl, nonan-2-yl, oxetan-3-yl and tetrahydrofuran-3-yl.

10. The compound of claim 1 , wherein the compound is of formula 1g:

in which:

R 2 is selected from: 1H-pyrrolo[2,3-b]pyridin-3-yl; 1H-indol-3-yl optionally substituted with 1 to 2 radicals independently selected from halo, methyl and methoxy; and phenyl optionally substituted with 1 to 2 radicals independently selected from methyl, halo and hydroxy;

R 4 is selected from isopropyl, sec-butyl, 1-hydroxypropan-2-yl, prop-1-en-2-yl, benzhydryl, nonan-2-yl, oxetan-3-yl and tetrahydrofuran-3-yl; and

Ra, Rb and Rc are independently selected from hydrogen, cyano, methyl, halo, —SO 2 CH 3 and trifluoromethyl.

11. The compound of claim 1 , wherein the compound is of the formula:

or a salt thereof.

12. The compound of claim 1 , wherein the compound is of the formula:

13. The compound of claim 1 , wherein the compound is of the formula:

or a salt thereof.

14. The compound of claim 1 , wherein the compound is of the formula:

15. The compound of claim 1 , wherein the compound is of the formula:

or a salt thereof.

16. The compound of claim 1 , wherein the compound is of the formula:

or a salt thereof.

17. The compound of claim 1 , wherein the compound is of the formula:

or a salt thereof.

18. The compound of claim 1 , wherein the compound is of the formula:

or a salt thereof.

19. The compound of claim 1 , wherein the compound is of the formula:

20. The compound of claim 1 , wherein the compound is of the formula: