Anti-Inflammatory, Analgesic and Antimicrobial Activity Studies of Novel 4, 6-Disubstituted-2-Amino-3-Cyanopyridines
Authors: Srinivasa Rao Atla, Neelakanta Rao Nagireddy, Rajendra Prasad Yejella.
Number of views: 216
A new series of 4-arylsubstituted-6-(p-hydroxyphenyl/p-aminophenyl)-3-cyano-2-amino pyridines were synthesized by an efficient one-pot cyclocondensation reaction of 4-amino/4-hydroxyacetophenone, aromatic aldehydes, malononitrile and ammonium acetate. The structures of these compounds were confirmed by IR, NMR (1H & 13C) and Mass spectral analysis. All the synthesized compounds were subjected to evaluation for their anti-inflammatory, analgesic and antimicrobial properties. The electro negativity of the substituents and their displacement on the 4- or 6-aryl ring of the 4,6-diaryl-3-cyano-2-aminopyridine nucleus (4a-p) influenced the anti-inflammatory and analgesic activity which was higher in the presence of electron releasing groups. The introduction of the p-hydroxyphenyl substituent in the 6-position of the 3-cyano-2-aminopyridine nucleus (4i-p) increased the anti-inflammatory and analgesic power, but there was no evidence of the relationship among the electronic characteristic of the substituents, their displacement on the 4-phenyl ring and the activity. These results indicated that 4k and 4p are more promising molecules as anti-inflammatory and analgesic agents. All compounds were also evaluated for their antimicrobial activity against variety of bacterial and fungal strains. Compounds 4b, 4f, 4h, 4j and 4p showed maximum activity comparable to the reference standards.