Synthesis and antimicrobial evaluation of 6-hydroxy-4,7-dimethoxybenzofuranylcarbonyl tethered annulated pyridines

2-Chloro-5-(6-hydroxy-4,7-dimethoxy-1-benzofuran-5-yl)carbonylpyridine-3-carbonitrile (3) was synthesized and its chemical reactivity was investigated toward a diversity of binucleophiles. Treatment of compound 3 hydrazine hydrate and phenylhydrazine produced pyrazolo3,4-bpyridines while isoxazolo5,4-bpyridine was obtained from reacting compound 3 with hydroxylamine. A diversity of pyrido2,3-dpyrimidines was synthesized from treatment of staring substrate 3 with some 1,3-N,N-binucleophiles. Treating compound 3 with some 1,4-binucleophiles including ethylenediamine, o-phenylenediamine, 2-aminophenol and 2-aminothiophenol furnished pyrido2,3-e1,4diazepine 12 and pyrido2,3-b1,5 benzodiazepine 13, pyrido2,3-b1,5benzoxazepine 14 and pyrido2,3-b1,5 benzothiazepine 15, respectively. The synthesize compounds shown remarkable effect against yeast and fungus, while compounds 4 and 7–11 exhibit excellent efficacy against all types of Gram + and Gram - bacteria. Structures of the produced compounds were established using analytical and spectroscopic tools.