InChI=1S/C18H18O5/c19-14-3-1-2-11(6-14)7-16-13(10-23-18(16)22)8-12-9-15(20)4-5-17(12)21/h1-6,9,13,16,19-21H,7-8,10H2/t13-,16+/m0/s1