Sesquiterpene Lactones from Artemisia argyi: Absolute Configuration and Immunosuppressant Activity

  • J Nat Prod. 2019 Jun 28;82(6):1424-1433. doi: 10.1021/acs.jnatprod.8b00791.
Jakob K Reinhardt  1 ,  Amy M Klemd  2 ,  Ombeline Danton  1 ,  Maria De Mieri  1 ,  Martin Smieško  3 ,  Roman Huber  2 ,  Thomas Bürgi  4 ,  Carsten Gründemann  2 ,  Matthias Hamburger  1
Affiliations
  • 1. Pharmaceutical Biology, Pharmacenter , University of Basel , Klingelbergstrasse 50 , 4056 Basel , Switzerland.
  • 2. Center for Complementary Medicine, Institute for Infection Prevention and Hospital Epidemiology, Faculty of Medicine , University of Freiburg , Breisacher Straße 115 B , 79106 Freiburg , Germany.
  • 3. Department of Molecular Modeling , University of Basel , Klingelbergstrasse 50 , 4056 Basel , Switzerland.
  • 4. Department of Physical Chemistry , University of Geneva , 30 Quai Ernest Ansermet , 1211 Geneva , Switzerland.
PMID: 31181920 DOI: 10.1021/acs.jnatprod.8b00791
Abstract

A library of extracts from Plants used in Chinese Traditional Medicine was screened for inhibition of T lymphocyte proliferation. An ethyl acetate extract from aerial parts of Artemisia argyi showed promising activity and was submitted to HPLC-based activity profiling to track the active compounds. From the most active time window, three guaianolides (1, 2, and 5) and two seco-tanapartholides (3 and 4) were identified and, in a less active time window, five new sesquiterpene lactones (8-11, 17), along with six known sesquiterpene lactones and two known Flavonoids. The absolute configurations of compounds 1, 2, 5-10, 13-15, 17, and 18 were established by comparison of experimental with calculated electronic circular dichroism (ECD) spectra. For seco-tanapartholides B (3) and A (4), ECD yielded ambiguous results, and their absolute configurations were determined by comparing experimental and calculated vibrational circular dichroism (VCD) spectra. Compounds 1-5 showed significant, noncytotoxic inhibition of T lymphocyte proliferation, with IC50 values between 1.0 and 3.7 μM.