Synthesis and Antibacterial Activity of Thiophenes

2-[Bis(methylthio)methylene]propanedinitrile 1a reacted in one-pot successively with piperidine, sodium sulfide, chloroacetonitrile, and potassium carbonate to afford 3-amino-5-(1-piperidinyl)-2,4-thiophenedicarbonitrile 2a. Similar reaction using the last three reagents with ethyl 2-cyano-3,3-bis(methylthio)acrylate 1b produced ethyl 4-amino-5-cyano-2-(methylthio)thiophene-3-carboxylate 2b. The synthesized compounds were characterized by using FT-IR, 1H-NMR, 13C-NMR, and mass spectral data. Antibacterial activities of the synthesized compounds are also reported.