Starting from 3-cyano-4,6-distyrylpyridin-2(1H)-thione (1), the compound N-(4-
chlorophenyl)-2-((3-cyano-4,6-distyrylpyridin-2-yl)thio)acetamide (2) was prepared.
Compound (2) underwent cyclization upon heating in ethanolic sodium ethoxide solution to
give the corresponding cyclized form 3-amino-N-(4-chlorophenyl)-4,6-distyrylthieno[2,3-
b]pyridine-2-carboxamide (3). The elemental analyses and spectroscopic data of compounds
(2) and (3) are in agreement with their proposed structures. Their insecticidal activity against
cowpea aphid, Aphis craccivora Koch, was studied. The results of insecticidal activity for
compounds (2) and (3) against the nymphs and the adults of the tested insects exhibited that
compounds (2) and (3) have a higher insecticidal activity than that of acetamiprid, a reference
insecticide, after 24 h of treatment.