The geometry of sinomenine vs. that of DXM is rather different. Dashed bonds are below the plane of the picture. Wedge bonds project out of the plane. I've attached a side-by-side comparison of the two molecules and a 3-d rendering of each. Crucially, the nitrogen atom is positioned very differently in each respective case. I would predict that sinomenine displays neither an antitussive nor a dissociative effect, at least not at sensible doses.
downwardsfromzero attached the following image(s):
DXM vs Sinomenine.jpg
(7kb) downloaded 41 time(s). DXM vs Sinomenine flipped.jpg
(7kb) downloaded 41 time(s). DXM3dVDW.jpg
(7kb) downloaded 41 time(s). Sinomenine3dVDW.jpg
(8kb) downloaded 41 time(s). “There is a way of manipulating matter and energy so as to produce what modern scientists call 'a field of force'. The field acts on the observer and puts him in a privileged position vis-à-vis the universe. From this position he has access to the realities which are ordinarily hidden from us by time and space, matter and energy. This is what we call the Great Work."
― Jacques Bergier, quoting Fulcanelli