A facile synthesis of 3,5-diaminopyrazole-4-carbothioamides and 3,5-diaminopyrazole-4-carboxylates

Simple and convenient synthesis of hitherto unknown 3,5-diaminopyrazole-4-c arbothioamides 3 as well as new ethyl 3,5-diaminopyrazole-4-carboxylates 7 is reported. The key intermediates were 2-cyanopropenethioamides 2 and 2-(e thoxycarbonyl)propene thio amides 5 which were readily obtained by reaction of phenyl isothiocyanate with 3-(2-acylhydrazino)-3-aminopropenenitriles 1 and ethyl 3-(2-acylhydrazino)-3-aminopropenoates 4 respectively. Intramole cular cyclization of compounds 2 afforded pyrazole-4-carbothioamides 3 whil e propenethioamides 5 gave pyrazole-4-carboxylates 7.