ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/CN.K/c1-2%3B/q-1%3B%2B1/file?format=sdf&get3d=True  -- InChI%3DInChI%3D1S/CN.K/c1-2%3B/q-1%3B%2B1 could not be loaded.