2-ethyl and 2-propyl isonicotinonitrile - intermediates for ethionamide and prothionamide

摘要

Title cpds. are of formula: (I) where R = CH3 or C2H5. They are prepd. by the reaction of isonicotinonitrile (II) with an aldehyde HCHO to give the 2-acetyl or propionyl isonicotinonitrile (III). This is hydrolysed with acid to give the corresponding amide (IV). Catalytic hydrogenation gives the 2-alpha-hydroxy alkyl cpd. (V) and treatment of this with POCl3 and catalytic reduction gives (I). They are converted to ethionamide or prothonamide by the action of H2S.