Two new phenylbutenoids from the rhizomes of cassumunar ginger and their α-glucosidase inhibitory activity.

An extract from the rhizomes of Cassumunar ginger (Zingiber purpureum Roscoe). was found to have significant α-glucosidase inhibitory activity with an IC₅₀ value of 6.3 µg/mL. Two new phenylbutenoids, cassudimin A (1) and cassumunol N (2), and seven known compounds (3–9) were isolated. Their structures and relative configurations of two new compounds were elucidated based on spectra interpretation. Compounds 1–3, 6–9 showed more potent α-glucosidase inhibitory activity than a positive control, acarbose (IC₅₀ = 168.0 µM). Dehydrozingerone (6) exhibited the most potent α-glucosidase inhibition with an IC₅₀ value of 8.3 μM. Compounds 7 and 9 were found in Z. purpureum rhizomes for the first time. [ABSTRACT FROM AUTHOR]