INS and type 2 diabetes mellitus: Two‐week oral administration of compound‐1 dose‐dependently and significantly reduced changes in the levels of glycosylated hemoglobin (GHb), plasma glucose, plasma insulin, and HOMA‐IR in male KK‐Ay/Ta Jcl mice (KK‐Ay mice), a model of obese type 2 diabetes with severe insulin resistance.