ERROR opening https://cactus.nci.nih.gov/chemical/structure/O%28c1c%28cccc1%29C2CC2%29CC/3%3DN/CCN%5C3/file?format=sdf&get3d=True  -- O%28c1c%28cccc1%29C2CC2%29CC/3%3DN/CCN%5C3 could not be loaded.