ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28C1%3DNC%3DCC%3DN1%29N2CCCC%28C2%29C3%3DCC%3DC%28C%3DC3%29O/file?format=sdf&get3d=True  -- CC%28C1%3DNC%3DCC%3DN1%29N2CCCC%28C2%29C3%3DCC%3DC%28C%3DC3%29O could not be loaded.