ERROR opening https://cactus.nci.nih.gov/chemical/structure/N%23CNC%28%3D%5BN-%5D%29%5BNH3%2B%5D/file?format=sdf&get3d=True  -- N%23CNC%28%3D%5BN-%5D%29%5BNH3%2B%5D could not be loaded.