ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1/2C8H8.U/c2*1-2-4-6-8-7-5-3-1;/h2*1-8H;/q2*-8;/file?format=sdf&get3d=True  -- InChI=1/2C8H8.U/c2*1-2-4-6-8-7-5-3-1;/h2*1-8H;/q2*-8; could not be loaded.