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