ERROR opening https://cactus.nci.nih.gov/chemical/structure/n2cncn2C%28C%28O%29C%28C%29%28C%29C%29%3DCc1ccc%28Cl%29cc1Cl/file?format=sdf&get3d=True  -- n2cncn2C%28C%28O%29C%28C%29%28C%29C%29%3DCc1ccc%28Cl%29cc1Cl could not be loaded.