Demeton methyl

Metasystox A trade name for demeton-methyl, C[Pg.257]

Delta Chemical Corporation, 225 Deltech Corporation, 225 Demeton-methyl, 50... 

Demeton—methyl is a mixture of 0,0-dimethyl 0- (2-ethyltliio)ethyl phosphorothioate (demeton—methyl O [8022-00-2] (46)) (bp 74°C at 20 Pa), soluble in water to 330 mg/L, and 0,0-dimethyl S-(2-ethylthio)ethyl phosphorothioate (demeton—methyl S) (bp 89°C at 20 Pa), soluble in water to 3.3 g/L. The rat oral LD5Qs are demeton O 180 and demeton S 40, 60 mg/kg. Demeton—methyl is a less persistent and safer systemic insecticide. 

These insecticides range from completely water-miscible compounds to essentially insoluble ones, as indicated in Table VI. Most highly water-soluble insecticides are systemic, that is, they are absorbed into the tissues of the growing crop, either through the leaves or through the roots. But some water-miscible compounds are so unstable that their toxicity is destroyed before systemic activity can be observed (12,18). Tepp, for example, has a half life in water of only 8 hours. While many other compounds in this class have only limited solubility in water, they are still effective systemics. Examples are demeton, methyl demeton, and phorate. 

Note. The name Demeton-methyl used to be applied to a mixture of demeton-S-methyl and demeton-O-methyl but this mixture has been replaced by demeton-S-methyl. 

The 0,0-dimethyl homologues of the derivatives discussed above, such as demeton-O-methyl (59) and demeton-S-methyl (60), attained importance because of their lower toxicity (Schrader, 1950d Lorenz et al., 1955 Miihlmann et al., 1954 Lorenz et al., 1955). Demeton-methyl, like its diethyl homologue discussed above, contains 70% of the thiono isomer (59) and 30% of the thiol isomer (60). 

Synonyms/Trade Names Demeton methyl 0,0-Dimethyl 2-ethylmercaptoethyl thiophosphate Metasystox Methyl mercaptophos Methyl systox ... 

Synonyms Demeton-methyl 0,0-Dimethyl-S,2-(ethylthio) ethyl phosphorothioate Methyl demeton Methyl mercaptophos Phosphorothioic acid, 0-[2-(ethylthio)ethyl] 0,0-dimethyl ester mixt. with S-[2-(ethylthio)ethyl] 0,0-dimethyl... 

Synonyms Bay 21097 Bayer 21097 Demeton-methyl sulfoxide Demeton-O-methyl sulfoxide Demeton-5 -methyl sulfoxide 0,0-Dimethyl 5 -(2-eththionylethyl) phospho-rothioate Dimethyl 5 -(2-eththionylethyl) thiophosphate 0,0-Dimethyl 5 -2-(ethylsulfi-nyl)ethyl phosphorothioate 0,0-Dimethyl S -2-(ethylsulfinyl)ethyl thiophosphate 0,0-Dimethyl iS-ethylsulphinylethyl phosphorothioate ENT 24964 dimethyl phosphorothioate Isomethylsystox sulfoxide Metaisosystox sulfoxide Metasystemox Metasystox-R Methyl demeton-O-sulfoxide Metilmercaptofosoksid Oxydemetonmethyl Phosphothioic acid 0,0-dimethyl S -2-(ethylsulfinyl)ethyl ester R 2170. 

Metamidofos estrella, see Methamidophos Metasol TK-100, see Thiabendazole Metasystemox, see Oj demeton-methyl Metasystox-R, see Oxydemeton-methyl Metaxon, see MCPA Metelilachlor, see Metolachlor Methachlor, see Alachlor Methamidophos Methanal, see Formaldehyde... 

DDVP, dichlorvos Demeton, Systox Demeton-methyl Metasystox Dialiphos... 

The second group, persistent pesticides, includes certain triazine herbicide derivatives, 2,4-dichlorophenoxycarbonic acids, and others (Buslovich 1986, Popovich and Burkatskaya 1986). Moderately persistent pesticides, the third class, include some systemic organophosphorus pesticides (such as demeton, demeton-methyl, Ekatin, and dimethoate), many synthetic pyrethroids, carbamates, and others. Examples of the fourth division, slightly persistent pesticides, are certain contact organophosphorus chemicals like parathion, methyl-para-thion, and others (Kagan 1977, 1981). 

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