A series of novel thiophene derivatives was designed, synthesized and their activities as competitive inhibitors of protein tyrosine phosphatase (PTPs) 1B (PTP1B) inhibitors were evaluated. All the compounds showed inhibitory potencies, and 10 of these exhibited moderate inhibitory activities with IC50 values less than 10μM. The activity of the most potent compound P28 (IC50= 2.1 μM) was 15 times higher than that of the hit compound P01. ...