ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/C16H16N2O4/c1-11-5-3-6-12%289-11%2918-16%2820%2922-14-8-4-7-13%2810-14%2917-15%2819%2921-2/h3-10H%2C1-2H3%2C%28H%2C17%2C19%29%28H%2C18%2C20%29/file?format=sdf&get3d=True -- InChI%3DInChI%3D1S/C16H16N2O4/c1-11-5-3-6-12%289-11%2918-16%2820%2922-14-8-4-7-13%2810-14%2917-15%2819%2921-2/h3-10H%2C1-2H3%2C%28H%2C17%2C19%29%28H%2C18%2C20%29 could not be loaded.