ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C6H8O4/c1-6(2)9-4(7)3-5(8)10-6/h3H2,1-2H3/file?format=sdf&get3d=True  -- InChI=1S/C6H8O4/c1-6(2)9-4(7)3-5(8)10-6/h3H2,1-2H3 could not be loaded.