The present invention is directed to compounds of Formula I:wherein X is CR1 or N； Y is CR2 or N； Z is NH or O； R1 is alkoxy, triazolyl, oxazolyl, isoxazolyl, oxadiazolyl, or pyrimidinyl； R2 is H, alkyl, or halo； R3 is H, alkyl, alkoxy, halo, triazolyl, oxazolyl, or pyrimidinyl； R4 is alkyl； R5 is pyridyl； benzoxazolyl； pyrimidinyl； pyridazinyl； quinoxalinyl； pyrazinyl； or quinazolinyl； wherein the pyridyl； benzoxazolyl； pyrimidinyl； pyridazinyl； quinoxalinyl； pyrazinyl； or quinazolinyl is optionally substituted with one or two substituents independently selected from the group consisting of alkyl, halo, or phenyl； and R6 is H or alkyl. Methods of making the compounds of Formula I are also described. The invention also relates to pharmaceutical compositions comprising compounds of Formula I. Methods of using the compounds of the invention are also within the scope of the invention.
