ERROR opening https://cactus.nci.nih.gov/chemical/structure/c3cccc2c3Oc1ccccc1C2C%28%3DO%29NC%28%3DO%29OCCCC/file?format=sdf&get3d=True  -- c3cccc2c3Oc1ccccc1C2C%28%3DO%29NC%28%3DO%29OCCCC could not be loaded.