Cyclotriol (also known as Zk 136295, ZK-136295, 14,21-Cyclo-19-norpregna-1,3,5(10)-triene-3,16,17-triol, (16-α,17-α)-, CCRIS 6527, 14α,17α-Ethano-1,3,5(10)-estratriene-3,16α,17-β-triol, (16-α,17-α)-14,21-Cyclo-19-norpregna-1,3,5(10)-triene-3,16,17-triol, Zk-136295, (+)-, (16α,17α)-14,21-Cyclo-19-norpregna-1,3,5(10)-triene-3,16,17-triol, 14,17α-Ethano-1,3,5(10)-estratriene-3,16α,17β-triol or 14,21-Cyclo-19-norpregna-1,3,5(10)-triene-3,16,17-triol, (16α,17α)-) is a substance of the steroid class.