ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/6CN.3K.Mn/c6%2A1-2%3B%3B%3B%3B/q6%2A-1%3B3%2A%2B1%3B/file?format=sdf&get3d=True -- InChI%3DInChI%3D1S/6CN.3K.Mn/c6%2A1-2%3B%3B%3B%3B/q6%2A-1%3B3%2A%2B1%3B could not be loaded.