ERROR opening https://cactus.nci.nih.gov/chemical/structure/c1ccc%28cc1%29C2CC%28%3DO%29N%28C2%29CC%28%3DO%29NN/file?format=sdf&get3d=True  -- c1ccc%28cc1%29C2CC%28%3DO%29N%28C2%29CC%28%3DO%29NN could not be loaded.