Guaianolides and unusual 3-oxa-guaianolides from Artemisia macrocephala

Yan-Rong Zhao; Guo-An Zou; Haji Akber Aisa

doi:10.1016/j.phytochem.2022.113108

Guaianolides and unusual 3-oxa-guaianolides from Artemisia macrocephala

Phytochemistry. 2022 May:197:113108. doi: 10.1016/j.phytochem.2022.113108. Epub 2022 Feb 4.

Authors

Yan-Rong Zhao¹, Guo-An Zou², Haji Akber Aisa³

Affiliations

¹ State Key Laboratory Basis of Xinjiang Indigenous Medicinal Plants Resource Utilization and the Key Laboratory of Plant Resources and Chemistry of Arid Zone, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, 830011, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
² State Key Laboratory Basis of Xinjiang Indigenous Medicinal Plants Resource Utilization and the Key Laboratory of Plant Resources and Chemistry of Arid Zone, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, 830011, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China. Electronic address: gazou@ms.xjb.ac.cn.
³ State Key Laboratory Basis of Xinjiang Indigenous Medicinal Plants Resource Utilization and the Key Laboratory of Plant Resources and Chemistry of Arid Zone, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, 830011, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China. Electronic address: haji@ms.xjb.ac.cn.

PMID: 35131640
DOI: 10.1016/j.phytochem.2022.113108

Abstract

Eight undescribed guaianolides (macrocephalolides A-H) and two known analogues (parishin C, artabsinolide E) were isolated from the whole plant of Artemisia macrocephala growing in Xinjiang, China. Their structures were determined on the basis of extensive spectroscopic analysis, with absolute configurations established by comparison of experimental and calculated ECD data, as well as confirmation of single-crystal X-ray diffraction crystallography. Macrocephalolides A-B featured an unusual type of 3-oxa-guaianolide with a cyclopentenone moiety. Macrocephalolides C-E possessed a dihydro-2H-pyran acetal segment, representing an unprecedented 2, 3-secoguaianolide skeleton with 6/7/5 tricyclic ring system in natural sesquiterpenes. The X-ray crystal structures of parishin C and artabsinolide E were reported for the first time.

Keywords: Artemisia griffithiana; Artemisia macrocephala; Asteraceae; ECD calculation; Guaianolides; Macrocephalolides A–H; X-ray diffraction.

MeSH terms

Artemisia* / chemistry
China
Crystallography, X-Ray
Molecular Structure
Sesquiterpenes* / chemistry

Substances

Sesquiterpenes