ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCCCCn1nc%28c2c1cccc2%29C%28%3DO%29Oc1cccc2c1cccc2/file?format=sdf&get3d=True  -- CCCCCn1nc%28c2c1cccc2%29C%28%3DO%29Oc1cccc2c1cccc2 could not be loaded.