1,4 substituted piperidinyl NMDA/NR2B antagonists

A compound having the formula:

• or a pharmaceutically acceptable salt thereof, wherein
• R1 is 2-benzimidazole, 2-imidazopyridine, purine, or 2-quinazoline, each optionally substituted with one to five substituents, each substituent independently being chloro, fluoro, bromo, C1-C4alkyl, trifluoromethyl, C1-C4alkylsulfonamide, hydroxy, or carboxy;
• R2 is phenyl, optionally substituted with one to five substituents, each substituent independently being chloro, fluoro, bromo, C1-C4alkyl, trifluoromethyl, C1-C4alkylsulfonamide, hydroxy, or carboxy;
• when R1 is 2-benzimidazole, L1 or L2 is not C1-C2alkyl, except when R1 is hydroxy-substituted 2-benzimidazole, L1 or L2 includes C1-C2alkyl;
• L1 and L2 are independently C1-C4alkyl, C1-C4alkenyl, C1-C4alkynyl, C1-C4alkoxy, aminoC1-C4alkyl, hydroxyC1-C4alkyl, carbonyl, cycloC3-C6alkyl or aminocarbonyl;
• and
• optionally substituted at any of the 2, 3, 5, or 6 positions independently with X, wherein X is hydroxy, amino, C1-C4alkylamino, di(C1-C4)alkylamino, C1-C4alkyl, C1-C4alkylester, —OCOOC1-C4alkyl, —NHCOOC1-C4alkyl, —OCONHC1-C4alkyl, C1-C4alkylcarbonate, or C1-C4alkylether.