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