| abstract |
Disclosed are chemical entities of formula (I) wherein X, Y, Z, R1, R3, R4, R5 and R6 are defined herein, as NR2B subtype selective receptor antagonists. Also disclosed are pharmaceutical compositions comprising a chemical entity of formula (I), and methods of treating various diseases and disorders associated with NR2B antagonism, e.g., diseases and disorders of the CNS, such as depression, by administering a chemical entity of formula I. |