Chemical constituents from the roots of Kadsura coccinea with their protein tyrosine phosphatase 1B and acetylcholinesterase inhibitory activities.

Kadsura coccinea (Lem.) A. C. Smith has been used as a tonic, decongestant, and digestive agent. The roots are also employed in traditional medicine to treat chronic enteritis, acute gastritis, duodenal ulcers, rheumatic pain in bone, and traumatic injuries. In the present study, we have described the biological evaluation of constituents from the roots of K. coccinea with PTP1B and AChE inhibitory activities for the first time in literature. A new compound (1), kadcoccilactone T, and 24 known ones (2‒25) were isolated and identified using spectroscopic methods. All the isolates were examined for PTP1B and AChE inhibitory activities. Compounds 4 and 8 expressed strong PTP1B inhibition with IC₅₀ values of 1.57 ± 0.11 and 3.99 ± 1.08 μM, respectively. Apparently, these compounds were further studied for PTP1B enzyme kinetic analysis. The result indicated that compounds 4 and 8 exhibited mixed-type inhibition with the Κ_i values of 4.97 and 3.26 µM, respectively.