InChI=1S/C15H20O4/c1-8-9-6-12-14(2,19-12)5-4-11-15(3,18-11)7-10(9)17-13(8)16/h10-12H,4-7H2,1-3H3/t10-,11+,12+,14+,15-/m0/s1