It's literally one query to https://scholar.google.com or any other search engine of choice, should I link to search results? Okay, so append ?q=[substance name] at the end of the URL. I don't mean to come off as rude, though. But it's really simple to do so, and it won't really serve any purpose to link to particular studies, either, as this could in turn add a potentially huge selection bias.
By the way, for more "obscure" in terms of scientific interest compounds see: beberine, theanine (aka l-theanine), vinpocetine. Particularly the last one. Same. These ones don't even have any synthetic counterparts which will share same or similar mechanism of action (there are other synthetic compounds targeting the same receptors, but they still represent very unique combinations of targets and also often have unique pharmacodynamics in relation to these targets).
So are you going to insist on the same for the original claim made here, too, or is this an isolated demand for rigor?
The person who makes the claim must justify it, not the readers.