ERROR opening https://cactus.nci.nih.gov/chemical/structure/c1ccc2c%28c1%29c3c%28%5BnH%5D2%29CNCC3/file?format=sdf&get3d=True  -- c1ccc2c%28c1%29c3c%28%5BnH%5D2%29CNCC3 could not be loaded.