ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C18H26/c1-3-7-15(8-4-1)17-11-13-18(14-12-17)16-9-5-2-6-10-16/h1,3-4,7-8,16-18H,2,5-6,9-14H2/t17-,18-/file?format=sdf&get3d=True  -- InChI=1S/C18H26/c1-3-7-15(8-4-1)17-11-13-18(14-12-17)16-9-5-2-6-10-16/h1,3-4,7-8,16-18H,2,5-6,9-14H2/t17-,18- could not be loaded.