ERROR opening https://cactus.nci.nih.gov/chemical/structure/%5BnH%5D1cc%28nc1%29C3%28Cc2c%28cccc2%29C3%29CC/file?format=sdf&get3d=True  -- %5BnH%5D1cc%28nc1%29C3%28Cc2c%28cccc2%29C3%29CC could not be loaded.