ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/2C2H5.Mg/c2%2A1-2%3B/h2%2A1H2%2C2H3%3B/q2%2A-1%3B%2B2/file?format=sdf&get3d=True -- InChI%3DInChI%3D1S/2C2H5.Mg/c2%2A1-2%3B/h2%2A1H2%2C2H3%3B/q2%2A-1%3B%2B2 could not be loaded.