S-Methyl

IUPAC name S-2-ethylthioethyl-O,O-dimethyl phosphorothioate Molecular formula C6H15O3PS2 Toxicity class USEPA I WHO lb 

Uses Demeton-s-methyl is a pale yellow oil that has a sulfur-like odor. It is a systemic and contact insecticide and acaricide. It kills insects that feed on plants by sucking juices. It is used to control aphids, sawflies, and spider mites in fruits, vegetables, potatoes, cereals, ornamentals, and forestry. Demeton-s-methyl replaces methyl demeton, a mixture of demeton-s-methyl and demeton-o-methyl sold as systox meta. Demeton-s-methyl is more toxic to insects than demeton-o-methyl. It is available as an emulsifiable concentrate.28,40 

Toxicity The acute oral LD50 of demeton-s-methyl for rats is 37.5 mg/kg, and the acute dermal LD50 for rats is 85 mg/kg. The acute LC50 for rats (4 hours) is 500 mg/m3 of air. Workers repeatedly exposed to demeton-s-methyl showed symptoms of headache, nausea, vomiting, diarrhea, sweating, and dizziness. In 

IUPAC name O, O-diethyl 0-2-isopropyl-6-methyl (pyrimidin-4-yl) phospho-rothioate 

Molecular formula C12H21N2O3PS Toxicity class USEPA II or III WHO II 

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There exist many naturally occurring sugars in which a hydroxyl group of a monosaccharide is replaced by an amino or a thiol group. These compounds, commonly called amino or thio sugars, play a wide variety of important biological roles. Representative examples of these classes are 2-acetamido-2-deoxy-a-D-glucose (1) and 7-(5-S-methyl-5-thio-/ -D-ri-bosyl)adenine (vitamin L2,2). The former is the product of hydrolysis of... 

CH4. Pteroenone, the name of the compound extracted from the sea butterfly referred to in Chapter 1, is a common name. The systematic name for this compound, though more descriptive of the elements it contains, is much longer 5(S)-methyl-6(/ )-hydroxy-7,9-dimethyl-7,9-dienc-4-undccanone. 

Conversion of tetra-0-acetyl-/3-D-ribopyranose into methyl 1-thio-/3-D-ribopyranoside, by the action of methanethiol and zinc chloride, with subsequent deacetylation, is accompanied by the formation of substantial proportions of methyl l,5-dithio-j8-D-ribopyranoside (55) and 4-S-methyl-4-thio-L-lyxose dimethyl dithioacetal (53), plus a trace of 5-S-methyl-5-thio-D-ribose dimethyl dithioacetal (56). Although similar treatment of tetra-O-acetyl-jS-D-ribofuranose for a short time produced the expected methyl 1-thio-jS-D-... 

Reaction of 2-methylene-1,3-dithietanes (256) with hydrazines affords 5-thiolpyrazoles (257) <90JHC567>. These last products were converted into 5-S-methyl pyrazoles (258) by methyliodide. Other authors <87JCS(P1)1945> have used a-aroyl-a-bromoketenedithioacetals to prepare 3(5),4-bis(alkylthio)pyrazoles. 

Adenine thiomethylpentoside (5-iS-methyl-5-thioadenosine) (11b) was first isolated from yeast, but was thought to be present in the tissues of many animals. Hydrolysis of this nucleoside gave adenine and 5-S-methyl-... 

The reaction of 5-iodopropionic acid has been studied and its biological implications discussed. "... 

Methano-5/5-cholestan-3-one (664) suffers photoreduction on irradiation in propan-2-ol, giving the 5jS-methyl-3-ketone (666) in a reaction which parallels that of some simple cyclohexanone analogues. The 4a,5a-methano-compound (667) unexpectedly also gave the 5/S-methyl ketone (666) as major product, with only a little of the 5a-methyl ketone (669). The reactions proceed through carbinyl radicals (665) or (668), and the symmetrical homoallylic radical (670) is postulated as providing a pathway for their interconversion. ... 

Me glycoside, S-Me, 2,3-isopropylidene Methyl 2,3-0-isopropylidene-5-S-methyl-5-thio-p-D-ribofuranoside C10H18O4S 234.316 [a]g -102 (c, 1.6 in CHCI3). 

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