Acid-Induced Rearrangement of Epoxygermacranolides: Synthesis of Furanoheliangolides and Cadinanes from Nobilin

Molecules

Matthias Hamburger¹  Marcel Kaiser²  Martin Smieško³  Isidor Ismajili⁴  Maria De Mieri⁴ 

[1] Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, 4000 Basel, Switzerland;;Department of Medical Parasitology &Molecular Modeling, Pharmazentrum, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland;Pharmaceutical Biology, Pharmazentrum, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland;

关键词: sesquiterpene lactones;    epoxygermacranolides;    acid-catalyzed rearrangement;    mechanism of reaction;    anti-protozoal activity;   

DOI  :  10.3390/molecules22122252

来源: DOAJ

【 摘 要 】

The acid-induced rearrangement of three epoxyderivatives of nobilin 1, the most abundant sesquiterpene lactone in Anthemis nobilis flowers, was investigated. From the 1,10-epoxyderivative 2, furanoheliangolide 5 was obtained, while the 4,5-epoxy group of 3 did not react. Conversely, when the 3-hydroxy function of nobilin was acetylated (12), the 4,5-epoxy derivative did cyclize into cadinanes (15 and 16) under Lewis acid catalysis. The reactivity of the 4,5- and 1,10-epoxy derivatives of nobilin (2 and 3) was compared with that of parthenolide, and rationalized on the basis of quantum chemical calculations. All isolated reaction products were fully characterized by spectroscopic and computational methods, and their in vitro anti-protozoal activity was evaluated. The paper could provide new insights into the biosynthesis of this class of natural products.

【 授权许可】

Unknown