ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%26%2361%3B1S/C4H4O4/c5-3%286%291-2-4%287%298/h1-2H%2C%28H%2C5%2C6%29%28H%2C7%2C8%29/b2-1-/file?format=sdf&get3d=True  -- InChI%3DInChI%26%2361%3B1S/C4H4O4/c5-3%286%291-2-4%287%298/h1-2H%2C%28H%2C5%2C6%29%28H%2C7%2C8%29/b2-1- could not be loaded.