2-S-ethyl-2-thio

CijHsbO Sj 2-S-Ethyl-2-thio-D-mannose diethyl dithioacetal EMANTA10 32 31 367 353... 

It is highly probable that the initial step in the overmercaptalation of 27 involves formation of a 2,3-acyloxonium ion however, formation of the 1,2-episulfonium ion 28 as an intermediate in the replacement of the 2-hydroxyl group has been established130 through the conversion of 27 into 3,4,5,6-tetra-0-benzoyl-2-S-ethyl-2-thio-D-man-nose ethyl phenyl dithioacetal (34) by the action of benzenethiol and an acid catalyst. The presence of an ethylthio group on C-2 in 34 was further established by conversion of 34 into 3,4,5,6-tetra-O-benzoyl-2-S-ethyl-2-thio-D-mannose dimethyl acetal. 

Tri-O-benzoyl-D-xylose diethyl dithioacetal reacts with eth-anethiol plus acid to form a 2-S-ethyl-2-thio-D-pentose diethyl dithioacetal137 of undetermined stereochemistry in view of the common stereochemical arrangements about C-l-C-4 in the D-gluco and D-xylo structures, this product probably has the D-lyxo arrangement. 

Raney nickel in aqueous ethanol normally acts to substitute hydrogen atoms in place of all of the alkyl-(or aryl- or other)thio groups present in a dithioacetal, without disturbing other substituents thus, the 2-S-ethyl-2-thio-D-pentose diethyl dithioacetal137 156, 5-S-ethyl-5-thio-D-arabinose diethyl dithioacetal145 (157), and 2,3,4,5-tetra-0-acetyl-6-S-acetyl-6-thio-D-galactose diethyl dithioacetal or its 6-thiocyanato analogue346 (158) react with Raney nickel to... 

Certain compounds, such as ethyl 2-S-ethyl-2-thio-a-D-man-... 

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