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Reactions of 1-(difluoromethanesulfinyl)pentafluorobenzene with sodium methoxide, sodium phenoxide, potassium hydrosulfide, and methylamine resulted in substitution of fluorine atom in the 4-position (in the reaction with methylamine, also in the 2-position). Treatment of the title compound with sodium hydroxide afforded pentafluorobenzene due to cleavage of the Carom‒S bond.

4-Cyano-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-5-methylimidazole (4) and its corresponding 5-cyano-4-methyl substituted isomer (5) have been obtained by ribosylation of 4(5)-cyano-5(4)-methylimidazole (3) via the mercuric cyanide method or by ribosylation of the trimethylsilyl derivative of 3. Treatment of 4 with methanolic ammonia, ammonium chloride in liquid ammonia and potassium hydrosulfide provided 4-cyano-1-β-D-ribofuranosyl-5-methylimidazole (6), 1-β-D-ribofuranosyl-5-methylimidazole-4-carboxamide (2) and 1-β-D-ribofuranosyl-5-methylimidazole-4-thiocarboxamide (11) respectively. Reaction of 6 with hydroxylamine afforded the corresponding 4-carboxamidoxime substituted nucleoside (13) which on catalytic reduction in the presence of ammonium chloride, was transformed into 1-β-D-ribofuranosyl-5-methylimidazole-4-carboxamidine (14) as hydrochloride salt.

3,3-Dimethyl-1-thia-3-silacyclobutane has been obtained by the reaction of Me2Si(CH2Cl)2 with potassium hydrosulfide in abs. ethanol. Intramolecular hydrosilylation of isomeric vinylthioethyldiethylsilanes, HEt2SiXSCHCH2 (X = CH(CH3) or CH2CH2) proceeds selectivity as α-addition to afford cyclic compounds, Et2 SiCH(CH 3 )SCHCH 3 and Et2 SiCH 2 CH 2 SC HCH3, respectively. This ring closure reaction is catalyzed by (Ph3P)3RhCl. The endocyclic SiC bond of 3,3-dimethyl-1-thia-3-silacyclobutane undergoes cleavage upon treatment with ethanolic KOH leading to Me2(EtO)SiCH2SCH3 and O(SiMe2CH2SCH3)2. The reaction of 3,3-dimethyl-1-thia-3-silacyclobutane with ethanolic HgCl2 involves ring opening and formation of a complex, O[SiMe2CH2S(HgCl2)CH2HgCl]2.

Synthesis of thiocysteine can be achieved by treating methoxycarbonylcysteine disulfide with potassium hydrosulfide. Thiocysteine rapidly decomposes in aqueous solutions to form cystine and sulfur.

Starting with AICA ribonucleoside the following nucleosides were prepared. Methyl 5-amino-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)imidazole-4-carboxylate (5) was converted into methyl 5-chloro-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)imidazole-4-carboxylate (6) via diazotization in the presence of cuprous chloride. Similarly, 5-amino-1-(2,3,5-tri-O-acetyl-beta-D-ribofuanosyl)imidazole-4-carbonitrile (9) was converted into 5-chloro-, 5-bromo-, and 5-iodo-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)imidazole-4-carbonitrile derivatives. These 5-halogenated imidazole nucleosides were treated with several nucleophiles such as ammonia, hydroxylamine, and hydrogen sulfide to provide, respectively, 5-haloimidazole-4-carboxamide, 5-haloimidazole-4-carboxamidoxime, and 5-haloimidazole-4-thiocarboxamide ribonucleosides. 5-Chloro- or 5-bromo-1-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)imidazole-4-carbonitrile was treated with potassium hydrosulfide to yield 5-mercapto-1-beta-D-ribofuranosylimidazole-4-thiocarboxamide (16). The catalytic reduction of 5-chloro- or 5-bromo-1-beta-D-ribofuranosylimidazole-4-carboxamidoxime provided 1-beta-D-ribofuranosylimidazole-4-carboxamidines as their hydrochloride and hydrobromide salts, respectively. These nucleosides were tested for in vitro antiviral, antifungal, and antibacterial activity. The 5-halo analogues of 1-beta-D-ribofuranosylimidazole-4-carboxamide showed significant antiviral activity whereas compound 16 was found inhibitory to fungi.

1. Nucleophilic cleavage of the thiirane ring in 3-(R-o-carboranyl)-1,2-epithiopropanes by sodium thiophenoxide, potassium hydrosulfide, N-methylaniline, and lithio-1-phenyl-o-carborane proceeds regioselectively at the sterically less-hindered carbon atom. 2. Treatment of 3-(R-o-carboranyl)-1,2-epithiopropanes with EtMgBr or Ph3P results in desulfurization to give the corresponding allyl-o-carboranes. 3. Treatment of 3-(R-o-carboranyl)-1,2-epithiopropanes with sodium ethoxide affords oligomeric polysulfides.

3-Hydroxypyridazine 1-oxide (I) and its methyl homologs (II), (III), and (IV) were submitted to electrophilic substitutions such as nitration and halogenation. Due to the additional polar effect of both N-oxide and hydroxyl groups, introduction of nitro group and halogen in 4-and/or 6-positions was successfully concluded. By heating with potassium hydrosulfide, nucleophilic substitution of the brominated compounds (XXXI and XXXVI) was also carried out, affording mercapto compounds (XXXII and XXXVII).

The reaction of diethylphosphoryl isothiocyanate with potassium hydrosulfide gave potassium diethoxyphosphinyldithiocarbamate (3a). This salt, with methylene bromide, afforded 2-diethoxyphosphinylimino-1,3-dithietane (5a) in high yield. In concentrated hydrochloric acid, 5a was hydrolyzed to 2-imino-1,3-dithietane which was isolated as a stable hydrochloride (7). The synthesis of some other N-Substituted 2-imino-1,3-dithietanes is also described.

The preparation of pent-2-en-4-ynylamine and pent-2-en-4-ynylthiol and their derivatives from 5-bromopent-3-en-1-yne was studied. Moreover, in connection with the preparation of the bromide, the rearrangement-bromination of vinylethynylcarbinol was found to give three isomeric bromides, 5-bromopent-trans-3-en-1-yne, 5-bromopent-cis-3-en-1-yne, and 3-bromopent-1-en-4-yne. Pent-2-en-4-ynylamine was obtained from 5-bromopent-3-en-1-yne by two methods, by the hydrolysis of the hexaminium salt and by the cleavage of N-(pent-2-en-4-ynyl)phthalimide. The reaction of 5-bromopent-3-en-1-yne with potassium hydrosulfide and the decomposition of ethyl pent-2-en-4-ynylxanthate by alcoholic ammonia gave pent-2-en-4-ynylthiol.

Thiochromono[3,2-d]pyrazoles are formed by the action of potassium hydrosulfide on 5-chloro-4-(o-chlorobenzoyl)pyrazoles. The action of Grignard reagents on them gave 4-dimethylaminopropylidenethiochromonopyrazoles, which are structural analogs of known medicinal substances.