Synthesis and antidiabetic activity of 3,6,7-trisubstituted-2-(1H-imidazol-2-ylsulfanyl)quinoxalines and quinoxalin-2-yl isothioureas.

Two series of 3,6,7-trisubstituted-2-(1H-imidazol-2-ylsulfanyl)-quinoxalines 2a-l and 2-(quinoxalin-2-yl)-isothioureas 3a-l were prepared. All the test compounds 2a-l and 3a-l were screened in vitro, in a RIN5F cell-based assay for glucose-dependent insulinotropic activity. A significant concentration and glucose-dependent insulin secretion effect was seen with compounds 2a-l and the insulinotropic activity of compound 2l was found to be identical to that of the standard compound (6,7-dichloro-2-trifluromethyl-3-(5-methyl-1,3,4-thiadiazo-2-ylsulfanyl)-quinoxaline (1)).