KS Lampe, writing in "Casarett and Doull's Toxicology", states that the
active principle in coprinus atramentarius is cyclopropanone hydrate.
For a review specific to coprinus, try: Michelot, D. "Poisoning by Coprinus
atramentarius." Nat. Toxins, 1992, 1(2), 73-80.
For poisonous mushrooms: Lampe, KS. "Toxic Fungi." Annu. Rev. Pharmacol.
Toxicol., 1979, 19, 85-104.
Hope this is a helpful start.
Andrew J. Sonderfan