ERROR opening https://cactus.nci.nih.gov/chemical/structure/%5BCu%2B2%5D.%5BO-%5DC%28%3DO%29C%28%5BO-%5D%29%3DO+/file?format=sdf&get3d=True -- %5BCu%2B2%5D.%5BO-%5DC%28%3DO%29C%28%5BO-%5D%29%3DO+ could not be loaded.