Related Experiment Video
Updated: Aug 3, 2026

Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry
Published on: October 2, 2016
Yangonindimers A-C, three new kavalactone dimers from Piper methysticum (kava)
Jia-Ling Song1,2, Bai-Lin Li1,2, Yao Yuan1,2
1a Program for Natural Products Chemical Biology, Key Laboratory of Plant Resources Conservation and Sustainable Utilization , South China Botanical Garden, Chinese Academy of Sciences , Guangzhou , China.
Abstract:
Three new kavalactone dimers, designated as yangonindimers A-C (1-3), along with one known analogue were isolated from the roots of Piper methysticum. Their structures were elucidated via extensive analysis of their 1D, 2D NMR and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units. Compounds 1-4 were evaluated for their cytotoxic activities against human tumour cell lines NCI-H46, SW480 and HepG2, but none showed significant activity.
More Related Videos
07:30A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
Published on: January 21, 2020
07:502D-HPLC-MS Technology Combined with Molecular Network for the Identification of Components in Tibetan Medicine Aconitum pendulum
Published on: December 8, 2023
Related Concept Videos
Conformations of Cyclohexane
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal tetrahedral value,...
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
Stereoisomerism of Cyclic Compounds
Prochirality
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
Opioid Analgesics: Morphine and Other Natural Cogeners