InChI=1S/C11H12O8P2.4Na/c1-7-6-10(18-20(12,13)14)8-4-2-3-5-9(8)11(7)19-21(15,16)17;;;;/h2-6H,1H3,(H2,12,13,14)(H2,15,16,17);;;;/q;4*+1/p-4