ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/2C2H5NO2.Cu/c2*3-1-2(4)5;/h2*1,3H2,(H,4,5);/q;;+2/p-2/file?format=sdf&get3d=True -- InChI=1S/2C2H5NO2.Cu/c2*3-1-2(4)5;/h2*1,3H2,(H,4,5);/q;;+2/p-2 could not be loaded.