ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C4H7NO2/c6-3-1-2-5-4(3)7/h3,6H,1-2H2,(H,5,7)/file?format=sdf&get3d=True -- InChI=1S/C4H7NO2/c6-3-1-2-5-4(3)7/h3,6H,1-2H2,(H,5,7) could not be loaded.