ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI=1S/C6H12N2/c1-2-6-4-7-5(1)3-8-6/h5-8H,1-4H2/t5-,6?/m0/s1/file?format=sdf&get3d=True  -- InChI=1S/C6H12N2/c1-2-6-4-7-5(1)3-8-6/h5-8H,1-4H2/t5-,6?/m0/s1 could not be loaded.