https://www.thevespiary.org/rhodium/Rhodium/chemistry/cocaine.analog.arecoline.html

There 's some recent research done concerning this subject, this may be some interesting bed-time literature.  Voilà, an additinal ref. for the .html at Rhodium's site.

http://l2.espacenet.com/espacenet/bnsviewer?CY=gb&LG=en&DB=EPD&PN=US6472422&ID=US+++6472422B2+I+

Patent US6472422

[.patent] US 6472422 [./patent] without .

I did the same before Barium gave me a crude remark..  

Thanks, the reference has been added to the end of that document.