Study of Artemisia kobstanica sesquiterpene lactones

Sesquiterpene lactones of wormwood Artemisia kobstanica Rzazade from the flora of Azerbaijan were studied for the first time. Three sesquiterpene lactones, C15H18O3, m. p. 171-172 °C (1), C15H20O4, m. p. 124-126 °C (2), C15H18O4, m. p. 202-203 °C (3). Based on physicochemical and spectral (IR and 1H NMR spectra) data, lactones 1 and 3 were identified with α-santonin and artemisinin, respectively. Substance 2 turned out to be new, for the first time isolated from the studied species of wormwood by merezolid. Based on the data obtained from the interpretation of IR and 1H NMR spectra, the structure of 3-keto-4,5-epoxy-8β, 7α, 11βH-germacr-10,15-ene-8,12-olide was proposed to it.