Name：3,5-Dioxo-7-thiocarboxy-hept-6-enoic acid

C8H8O5S
Exact Mass: 216.01
Mol. Wt.: 216.21
m/e: 216.01 (100.0%), 217.01 (9.9%), 218.01 (5.5%)
C, 44.44; H, 3.73; O, 37.00; S, 14.83