ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/C4H8O4/c5-1-3%287%294%288%292-6/h3%2C5-7H%2C1-2H2/file?format=sdf&get3d=True  -- InChI%3DInChI%3D1S/C4H8O4/c5-1-3%287%294%288%292-6/h3%2C5-7H%2C1-2H2 could not be loaded.