ERROR opening https://cactus.nci.nih.gov/chemical/structure/C1%28%3DNNN%28C%28%3DN%29N%29N%29N%3DNN%3DN1.O/file?format=sdf&get3d=True  -- C1%28%3DNNN%28C%28%3DN%29N%29N%29N%3DNN%3DN1.O could not be loaded.