Monoterpene-chalcone conjugates and diarylheptanoids isolated from the seeds of Alpinia katsumadai Hayata with cytotoxic activity.

Five undescribed monoterpene-chalcone conjugates (1-5), one undescribed hypothetical precursor of diarylheptanoid (6), two undescribed diarylheptanoids (7-8), and fourteen known compounds (9-22) were isolated from the seeds of Alpinia katsumadai. Their structures were elucidated through the interpretation of HRESIMS, NMR, ECD, and X-ray diffraction data. MTT assays on human cancer cell lines (HepG2, A549, SGC7901, and SW480) revealed that compounds 3-8, 11, and 13 exhibited broad-spectrum antiproliferative activities with IC50 values ranging from 3.59 to 21.78 µM. B cell lymphoma 2 was predicted as the target of sumadain C (11) by network pharmacology and verified by homogeneous time-resolved fluorescence assay and molecular docking.

Terpenoids from Alpinia galanga and their acetylcholinesterase inhibitory activity.

A new labdane diterpene (1), two new norsesquiterpenoids (2-3), as well as eight known terpenoids (4-11) were isolated from the seeds of Alpinia galanga (Zingiberaceae). Their structures and absolute configurations were elucidated by 1D, 2D NMR, MS, and comparison of their experimental and calculated electronic circular dichroism (ECD). The acetylcholinesterase (AChE) inhibitory activities of all the isolated compounds (1-11) were evaluated and the result showed that compounds 6 and 9 had inhibitory activity against AChE, with IC50 values at 295.70 and 183.91 µM, whereas other compounds did not show any inhibitory activity.

Lignans and Flavonoids from Cajanus cajan (L.) Millsp. and Their α-Glucosidase Inhibitory Activities.

A pair of new lignan conformers (1-2), one new flavonoid glycoside (3), as well as nineteen known compounds were purified from the twigs and leaves of Cajanus cajan (L.) Millsp.. The planar structures of the unknown compounds were determined via NMR and high-resolution mass spectrometry, while their absolute configurations were elucidated via comparison between their experimental and calculated electronic circular dichroism (ECD) values. All the isolated compounds were assayed for their α-glucosidase inhibitory activities. The results demonstrated that compounds 8-12, 15-16, 18-19, 21-22 had strong inhibition activities, with compound 10 (IC50 =0.4±0.21 µM) most active. The structure-activity relationships were preliminarily summarized. Enzyme kinetics showed that compounds 8, 9, 15-16, 18-19, 21-22 were non-competitive inhibitors and compounds 10-12 were anti-competitive ones.