ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C5H6N2O4/c8-3(9)1-2-4(10)7-5(11)6-2/h2H,1H2,(H,8,9)(H2,6,7,10,11)/file?format=sdf&get3d=True  -- InChI=1S/C5H6N2O4/c8-3(9)1-2-4(10)7-5(11)6-2/h2H,1H2,(H,8,9)(H2,6,7,10,11) could not be loaded.