ERROR opening https://cactus.nci.nih.gov/chemical/structure/c1%3Dcc%3Dc2c%3Dcc%3Dcc2%3Dc1/file?format=sdf&get3d=True  -- c1%3Dcc%3Dc2c%3Dcc%3Dcc2%3Dc1 could not be loaded.