ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%3DC4Nc3c%28cc%28OCCCCc1nnnn1C2CCCCC2%29cc3%29CC4/file?format=sdf&get3d=True  -- O%3DC4Nc3c%28cc%28OCCCCc1nnnn1C2CCCCC2%29cc3%29CC4 could not be loaded.