[1,2,4]triazolo[1,5and#8208;A]pyrimidine compounds as PDE2 inhibitors

A compound having the Formula (I)

• or a stereoisomeric form thereof, wherein
• RA is selected from the group consisting of H, CH3, CN, and CHF2;
• RB is a radical selected from the group consisting of (a), (b) and (c):
• wherein
• R1 is H, F or CH3;
• R2 is H or C1-4alkyl, in particular methyl or n-butyl;
• with the proviso that when R2 is H, then R1 is F or CH3;
• R3 is Ar, Het, or Ar-C2-4alkenyl;
• wherein
• Ar represents phenyl or naphthyl, each optionally substituted with 1, 2 or 3 substituents, each independently selected from the group consisting of halo;
• CN;
• NR2AR2B wherein R2A and R2B are each independently selected from H and CH3;
• OH;
• C1-6alkyl optionally substituted with 1, 2 or 3 independently selected halo substituents;
• C1-6alkyl substituted with CN;
• C3-6cycloalkyl;
• C1-6alkyloxy optionally substituted with 1, 2 or 3 independently selected halo substituents;
• and pyrazolyl;
• Het represents
• (i) a 5-membered heteroaryl selected from the group consisting of 1H-pyrrolyl;
• thienyl;
• furanyl;
• 1H-pyrazolyl;
• 1H-imidazolyl;
• 1,2-oxazolyl;
• 1,3-oxazolyl;
• and thiazolyl;
• each of which may be optionally substituted with 1, 2 or 3 substituents each independently selected from the group consisting of halo;
• C1-4alkyl optionally substituted with 1, 2, or 3 independently selected halo substituents;
• NR3AR3B wherein R3A and R3B are each independently selected from H and CH3;
• and furan-2-yl;
• or
• (ii) a 6-membered heteroaryl selected from the group consisting of pyridyl, pyrimidinyl, pyrazinyl, and pyridazinyl;
• each of which may be optionally substituted with 1, 2 or 3 substituents each independently selected from the group consisting of halo;
• OH;
• CN;
• NR4AR4B wherein R4A and R4B are each independently selected from H and CH3;
• C1-4alkyl optionally substituted with 1, 2 or 3 independently selected halo substituents;
• C1-4alkyl substituted with OH;
• C3-6cycloalkyl;
• C3-6cycloalkyloxy;
• C1-4alkyloxy optionally substituted with 1, 2 or 3 independently selected halo substituents;
• and
• C1-4alkyloxyC1-4alkyl;
• or
• (iii) a 8- to 10-membered bicyclic partially unsaturated heterocyclyl selected from the group consisting of 2,3-dihydro-1-benzofuranyl;
• 2H-chromenyl;
• 3,4-dihydro-2H-chromenyl;
• 2,3-dihydro-1H-indolyl optionally substituted at the 1-position with C1-4alkyl, methyl sulfonyl, 1-acetyl, or fluoroacetyl;
• 2,2-difluoro-1,3-benzodioxolyl;
• 1,3-benzodioxolyl optionally substituted with a methyl substituent;
• 3,4-dihydro-2H-1,4-benzoxazinyl optionally substituted with C1-4alkyl;
• 5,6,7,8-tetrahydroimidazo[1,2-a]pyridinyl;
• 5,6,7,8-tetrahydroquinolinyl optionally substituted with a halo substituent;
• and 2,3-dihydropyrazolo[5,1-b][1,3]oxazolyl;
• or
• (iv) a 9- to 10-membered bicyclic heteroaryl selected from the group consisting of 1-benzofuranyl;
• 1-benzothiophenyl;
• 1H-indolyl;
• 1,3-benzoxazolyl;
• 1,3-benzothiazolyl;
• indolizinyl;
• 1H-benzimidazolyl;
• imidazo[1,2-a]pyridinyl;
• pyrazolo[1,5-a]pyridinyl;
• 1H-thieno[2,3-c]pyrazolyl;
• imidazo[2,1-b]thiazolyl;
• pyrrolo[2,3-c]pyridinyl;
• thieno[3,2-b]pyridinyl;
• quinolinyl;
• isoquinolinyl;
• quinoxalinyl;
• 1,8-naphthyridinyl;
• and 1,6-naphthyridinyl;
• each of which may be optionally substituted with 1 or 2 substituents each independently selected from the group consisting of halo;
• OH;
• NR5AR5B wherein R5A and R5B are each independently selected from H and CH3;
• C1-4alkyl optionally substituted with 1, 2 or 3 independently selected halo substituents;
• and C1-4alkyloxy optionally substituted with 1, 2 or 3 independently selected halo substituents;
• with the proviso that the compound is not
• or an N-oxide, or a pharmaceutically acceptable salt or a solvate thereof.