Purmorphamine, under the IUPAC name 9-Cyclohexyl-N-[4-(4-morpholinyl)phenyl]-2-(1-naphthalenyloxy)-9H-purin-6-amine, is a cell-permeable 6,9-trisubstituted purine which directly binds and activates Smoothened (in HEK293T cell:IC50= ~ 1.5 μM ).So it has been shown to activate the Hedgehog (Hh) signaling pathway which is important for regulating embryonic patterning, stem cell renewal, and tissue regeneration. I found the answer from the website of BOC Sciences.