39856-16-1 GS 13007 GS-13007 Phosphorothioic acid, S-((5-methoxy-2-oxo-1,3,4-thiadiazol-3(2H)-yl)methyl) O,O-dimethyl ester S-((2-Methoxy-5-oxo-delta(2)-1,3,4-thiadiazolin-4-yl)methyl) O,O-dimethyl phosphorothioate