methidathion ; o,o-dimethyl s-(2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl) phosphorodithioate ; o,o-dimethyl-s-(5-methoxy-1,3,4-thiadiazolinyl-3-methyl) dithiophosphate ; 3-dimethoxyphosphinothioylthiomethyl-5-methoxy-1,3,4-thiadiazol-2(3h)-one ; dithiophosphoric acid o,o'-dimethyl-s-((2-methoxy-1,3,4-thiadiazol-5(4h)-on-4-yl)methyl) ester ; dithiophosphoric acid o,o'-dimethyl-s-((5-methoxy-1,3,4-thiadiazol-2(3h)-one-3-yl)methyl) ester ; o,o'-dimethyl-s-((2-methoxy-1,3,4-thiadiazol-5(4h)-one-4-yl)methyl) dithiophosphate ; o,o-dimethyl phosphorodithioate, s-ester with 4-(mercaptomethyl-2-methoxy-1,3,4-thiadazolin-5-one) ; o,o-dimethyl-s-((2-methoxy-1,3,4(4h)thiodiazol-5-on-4-yl)-methyl)-dithiofosfaat ; o,o-dimethyl-s-(2-methoxy-1,3,4-thiadiazol-5(4h)-onyl-(4)-methyl) phosphorodithioate ; o,o-dimethyl-s-(2-methoxy-1,3,4-thiadiazol-5-(4h)-onyl-(4)-methyl)-dithiophosphat ; o,o-dimetil-s-((2-metossi-1,3,4-(4h)-tiadiazol-5-on-4-il)-metil)-ditiofosfato ; phosphorodithioic acid s-((5-methoxy-2-oxo-1,3,4-thiadiazol-3(2h)-yl)methyl) o,o-dimethyl ester ; phosphorodithioic acid, o,o-dimethyl ester, s-ester with 4-(mercaptomethyl)-2-methoxy-delta(sup 2)-1,3,4-thiadiazolin-5-one ; s-((2-methoxy-5-oxo-1,3,4-thia-diazolin-4-yl)methyl)dimethylphosphorothiolothionate ; s-((5-methoxy-2-oxo-1,3,4-thiadiazol-3(2h)-yl)methyl) o,o-dimethyl phosphorodithioate ; s-(2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-methyl) ; s-(2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-methyl) dimethyl phosphorothiolothionate