InChI=1S/C14H22O4/c15-13(16)11-9-7-5-3-1-2-4-6-8-10-12-14(17)18/h3,5,7,9H,1-2,4,6,8,10-12H2,(H,15,16)(H,17,18)/b5-3-,9-7+