ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DN%28%3DO%29c1ccc%28cc1%29/N%3DN/c2c3ccccc3ccc2O/file?format=sdf&get3d=True  -- O%3DN%28%3DO%29c1ccc%28cc1%29/N%3DN/c2c3ccccc3ccc2O could not be loaded.