ERROR opening https://cactus.nci.nih.gov/chemical/structure/CC%28C%29N%28CCC%29CCc1c%5BNH%5Dc2cccc%28O%29c21/file?format=sdf&get3d=True  -- CC%28C%29N%28CCC%29CCc1c%5BNH%5Dc2cccc%28O%29c21 could not be loaded.