ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC3c1c%28cccc1%29C%28OCC%29c2c%28cccc2%29N3C/file?format=sdf&get3d=True  -- O%3DC3c1c%28cccc1%29C%28OCC%29c2c%28cccc2%29N3C could not be loaded.