That is much clearer. However, you are asking a different question now, than you did before.
You want to relate the structure of this pharmaceutical to its receptor in the human brain. You have to know the receptor first, and that might not be known, at this point. Although its likely it interacts with the same receptor its analogues interact with. You also want the literature that relates the theoretical interactions of various charged groups between proteins. These sort of discussions are typically found in undergraduate classrooms, but when they appear in peer-reviewed journals, they are conducted by Ph.D. level investigators, for a Ph.D. level reader. You will find that the description is very technical, at least I often do. Also, people try to verify these interactions, often with targeted NMR or X-ray crystallography. Nevertheless, you will have to keep searching on your own for the topics you need. You can use the authors from the papers above, to find other papers they've written, to see if you find a more expanded treatment of the topic you want.