ERROR opening https://cactus.nci.nih.gov/chemical/structure/Cn1cnc2c1c%28%3DO%29%5BnH%5Dc%28%3DO%29n2C/file?format=sdf&get3d=True  -- Cn1cnc2c1c%28%3DO%29%5BnH%5Dc%28%3DO%29n2C could not be loaded.