ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/4C9H8O4.2Cu/c4*1-6(10)13-8-5-3-2-4-7(8)9(11)12;;/h4*2-5H,1H3,(H,11,12);;/q;;;;2* 2/p-4/file?format=sdf&get3d=True  -- InChI=1S/4C9H8O4.2Cu/c4*1-6(10)13-8-5-3-2-4-7(8)9(11)12;;/h4*2-5H,1H3,(H,11,12);;/q;;;;2* 2/p-4 could not be loaded.