Fluorine-containing heterocycles: synthesis and some reactions of new 3-amino-2-functionalized-6-(2'-thienyl)-4-trifluoromethylthieno [2,3-b]pyridines.

3-Cyano-6-(2'-thienyl)-4-trifluoromethylpyridine-2(1H)-thione (2) was prepared and reacted with chloroacetone or phenacyl bromide to yield the 2-acetyl or benzoyl-3-amino-6-(2'-thienyl)-4-trifluoromethylthieno[2,3-b]pyridines (3a, b). In contrast, the reaction of 2 with chloroacetamide or its N-aryl derivatives gave the corresponding 2-carbamoylmethyl thiopyridines 4a-c. Upon treatment of these educts with K2CO3 or C2H5ONa in ethanol, they underwent intramolecular Thorpe-Ziegler cyclization to afford 3-amino-2-carbamoyl-6-(2'-thienyl)-4-trifluoromethyl-thieno[2,3-b]pyridine (5a) and its N-aryl analogs 5b, c. Compounds 5a-c underwent some reactions to yield new pyrido[3',2':4,5]thieno[3,2-d]pyrimidines and pyrido[3',2':4,5]thieno[3,2-d][1,2,3] triazines.

Nitriles in heterocyclic synthesis. Part III: New sulpha drugs related to cyanopyridine derivatives.

4-Hydroxyacetophenone (1) was reacted with cinnamonitrile derivatives (2-6) to give 3-cyano-4-(substituted phenyl)-6-(p-hydroxyphenyl)-pyridines (7-11). Interaction of compounds 7-9 with 4'-substituted heterocyclo-benzenesulphonyl diazonium chloride gave the corresponding 3-cyano-4-(substituted phenyl)-6-(3'-azobenzene sulphonamido-4'-hydroxyphenyl) pyridines (12-29). The corresponding iron (III) copper (II) and mercury (II) chelates were also prepared in a 1:2 metal-to-ligand ratio. All the synthesized compounds were characterized on the basis of microanalysis, IR and 1H-NMR spectrometry.