Hydrangeic acid is a stilbenoid found in the leaves of Hydrangea macrophylla.Hydrangeic acid from the processed leaves of Hydrangea macrophylla var. thunbergii as a new type of anti-diabetic compound. Hailong Zhang, Hisashi Matsuda, Chihiro Yamashita, Seikou Nakamura and Masayuki Yoshikawa, European Journal of Pharmacology, Volume 606, Issues 1–3, 15 March 2009, Pages 255–261,
Hydrangeic acid is being investigated as a possible antidiabetic drug as it significantly lowered blood glucose, triglyceride and free fatty acid levels in laboratory animals.
See also Lunularic acid, the corresponding dihydrostilbenoid also found in H. macrophylla
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