ERROR opening https://cactus.nci.nih.gov/chemical/structure/c12c%28ncn1CCOCP%28O%29%28O%29%3DO%29c%28ncn2%29N/file?format=sdf&get3d=True  -- c12c%28ncn1CCOCP%28O%29%28O%29%3DO%29c%28ncn2%29N could not be loaded.