Why Do Ace Attorney Games Sometimes Invent Chemicals?

Why do you think the series used fake poison names at times, such as Asphyxion (Ace Attorney Investigations 2), atroquinine (Apollo Justice: Ace Attorney), etc.? Why not just use real world poisons? It is not like they are tied to any one company.

The only reason I could think would be so these fake poisons could have any effects they wanted them to have, such as Asphyxion needing to be mixed with Ubiquium (another made up chemical) to produce poison.

Any other ideas?