| abstract |
(57) [Problem] To provide a compound having tyrosine phosphatase inhibitory activity and having excellent stability under physiological conditions. SOLUTION: General formula (1): (Wherein, R represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an acetyl group), and a compound represented by the general formula (1) as an active ingredient. A therapeutic agent for diabetes, comprising, as active ingredients, a tyrosine phosphatase inhibitor, and a compound represented by the general formula (1) or a pharmaceutically acceptable salt thereof. |