ERROR opening https://cactus.nci.nih.gov/chemical/structure/CCCN1C%28%3DO%29C%28%3DCN2C1%3DNC%28%3DN2%29N%29C/file?format=sdf&get3d=True  -- CCCN1C%28%3DO%29C%28%3DCN2C1%3DNC%28%3DN2%29N%29C could not be loaded.