Hydrogen sulfide in pyridine

The method described is adapted from the procedures of Kym 3 and Engelhardt, Latschinoff, and Malyscheff.4 Thio-benzoic acid has been prepared by the reaction of benzoyl chloride with potassium sulfide,4 hydrogen sulfide in pyridine,6 6 and magnesium bromide hydrosulfide.7 It is formed from dibenzoyl disulfide with potassium hydrosulfide,4 potassium hydroxide,4 8 and ammonia.9 It is also formed from dibenzoyl sulfide, from phenyl benzoate, and from benzoic anhydride with alcoholic potassium hydrosulfide.4 It has been obtained from dibenzoyl sulfide and hydrogen sulfide,10 carbon oxysulfide and phenyl-magnesium bromide,11 12 dibenzyl disulfide and sodium ethoxide,13 benzyl chloride and sulfur in the presence of potassium hydroxide,14 and benzylthiosulfuric acid and alkali.18 16... 

Treatment of 5-alkyl(or aryl)amino-3-alkylthio-l,2,4-thiadiazoles with hydrogen sulfide in pyridine-triethylamine, or with sodium in liquid ammonia, yields 1-substituted dithiobiurets.182 Since, in the... 

After glycosylation with sphingosine the azide group is reduced to an amine. Hydrogen sulfide in pyridine / water hereby acts as reducing reagent. Next stearic acid (75) has to be connected to the amine - a peptide bond is formed. 

These nitriles, when treated with hydrogen sulfide in pyridine and triethylamine, give 2-amino-3-cyano-l, 6,6a/S IV-trithiapentalenes (Eq. 29).48... 

Methylisothiazole-5-carboxylic acid has also been prepared by alkaline hydrolysis of the 5-nitrile. The 5-acids decarboxylate readily at or near their melting points but otherwise behave normally, forming acid chlorides, esters, amides, hydra-zides, and nitriles. The esters undergo the Claisen condensation to form ]8-ketoesters, and the nitriles form thioamides with hydrogen sulfide in pyridine. An anomalous reaction is the reduction of 5-cyano-... 

Partial reduction of aromatic polynitro compounds leads to nitro amines. The most successful reagents are the alkali metal or ammonium sulfides in aqueous alcoholIn some instances, sodium bicarbonate combined with sodium sulfide gives better results because of the formation of sodium hydrosulfide, which is believed to be the main reducing agent. Also, aqueous methanol is preferred to aqueous ethanol. Nitro compounds that are sparingly soluble in alcohol solutions may be reduced by hydrogen sulfide in pyridine solution. ... 

Thus, facile conversion of acetylated AICN-riboside into 7-ribosyl-6-sulfanylpurine 1 has been accomplished with diethoxymethyl acetate and hydrogen sulfide in pyridine. " ... 

A -Alkyl(thiocarbamoyl)]pyrazines have also been obtained by heating the 2-(A -alkylcarbamoyl)pyrazine with phosphorus pentasulfide and potassium sulfide in xylene at 100° (1268) and 2-amino-3-carbamoyl-5,6-diphenylpyrazine refluxed with phosphorus pentasulfide in pyridine gave 2-amino-5,6-diphenyl-3-thiocarbamoylpyrazine and the 3-A -butyl(thiocarbamoyl) analogue was prepared similarly (455). 2-Amino-5-chloro-3-(C-imino-C-methylthiomethyl)pyrazine with hydrogen sulfide in pyridine gave 2-amino-5-chloro-3-thiocarbamoylpyrazine (1218). 

A 1-thiolactose was prepared by treating /3-lactose with hydrogen sulfide in pyridine for three days. ... 

Treatment of arylbis(dimethylamino)cyclopropenylium chloride with a solution of hydrogen sulfide in pyridine afforded 2-aryl-3-dimethylaminocyclopropenethioncs 3 in 77-87% yield. ... 

The unambiguous synthesis of TO was accomplished starting from T. Treatment with iodomethane and then with hydrogen sulfide in pyridine, afforded the dithioester. This compound was oxidized with m-chloroperbenzoic acid in chloroform at 0 C, to give the thionoxide. This was reacted with morpholine in methanol and from the reaction... 

Treatment of the 2,5 -anhydride 17 with liquid hydrogen sulfide in pyridine gave the 2-thiono-pyrimidine, which could be oxidatively desulfurized to give the 2 -deoxy-4-pyriniidinone nucleoside. ... 

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