[Antitubercular agents. LIV. 3-Alkyl(or -alkyl) thio-2,5-pyrazindicarboxamides].

From 5-cyano-3-chloro-2-pyrazinecarboxamide) (II) hydrolysis in acid medium) yielded 3-chloro-2,5-pyrazinedicarboxamide (III), which in a reaction with sodium hydrogensulfide in dimethyl-formamide) yielded 3-mercapto-2,5-pyrazinedicarboxamide (IV). This compound through condensations with alkyl- and arylhalogenides in triethylamine) yielded 3-alkyl(or aryl) thio-2,5-pyrazinedicarboxamides of type I. The structure of compounds was confirmed by elemental analysis, IR and 1H NMR spectra. A microbiological evaluation was carried out; the antituberculous effect of these compounds is not higher than that of pyrazinamide.