Addition‐cyclisations of ethoxycarbonyl isothiocyanate with hydrazine derivatives as a source of thiadiazoles and triazoles

Abstract

Ethoxycarbonyl isothiocyanate reacts additively with hydrazine, ethoxycarbonylhydrazine, as well as amino‐ and 1,2‐diaminoguanidine. Simultaneous or subsequent cyclisation of the resulting 1:1‐ or 2:1‐adducts in acidic or alkaline media yields substituted 1,3,4‐thiadiazoles or 1,2,4‐triazoles, respectively.

Chemistry and heterocyclization of dithiobiurea and thioureidoalkylthiourea

“…The interaction of guanidine derivatives 55 and ethoxycarbonyl isothiocyanate under mild conditions afforded the thiadiazole derivatives 57 (Scheme ) [82].…”

“…The action of alkali or hydrazine on 4 produced moderate yields 3‐amino‐5‐mercapto‐1,2,3‐triazole 92 or 4‐amino‐3‐hydrazino‐5‐mercapto‐1,2,4‐triazole 93 (Scheme ) [82].…”

Synthesis of novel pyridazine derivatives as potential antimicrobial agents

“…[1] Also, phenethyl isothiocyanate and sulforaphane inhibit carcinogenesis and tumorigenesis in certain circumstances. [2] Several methods were employed in the synthesis of isothiocyanates, including the reaction of amine derivatives with carbon disulfide [3][4][5][6][7][8] or thiophosgene, [9][10][11] treatment of the carboxylic acid derivatives with ammonium thiocyantes [12][13][14][15] and pyrolysis of thiourea derivative in o-dichlorobenzene. [16] In addition, many natural isothiocyanates from plants were used as anticancer agents [17,18] and produced by enzymatic conversion of metabolites called glucosinolates.…”

Synthesis of 1,3,4-Thiadiazole, 1,3,4-Thiadiazine, 1,3,6-Thiadiazepane and Quinoxaline Derivatives from Symmetrical Dithiobiureas and Thioureidoethylthiourea Derivatives

“…Several authors have investigated the heterocyclization of 1,6-disubstituted dithiobiureas in basic or acidic media [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. We report herein the results of our recent investigations on the reactions of symmetrical dithiobiureas as well as thioureidoethylthiourea derivatives with both chloranil ( 10a ) and bromanil ( 10b ).…”