The present invention in one embodiment relates to a compound of Formula (I); or a pharmaceutically acceptable salt thereof, wherein: each of R
1
and R
2
is independently selected from —CH
3
and —CD
3
; R
3
is hydrogen or deuterium; each of Z
1
, Z
2
and Z
3
is independently selected from hydrogen and deuterium; each Z
4
is hydrogen or deuterium; each Z
5
is hydrogen or deuterium; and each Z
6
is hydrogen or deuterium.
本发明在一种实施例中涉及化合物(I)的一种;或其药学上可接受的盐,其中:R1和R2各自独立地选自—
CH3和—CD3;R3是氢或
氘;Z1、Z2和Z3各自独立地选自氢和
氘;每个Z4是氢或
氘;每个Z5是氢或
氘;每个Z6是氢或
氘。