• Guaianolides from Centaurea sinaica 

      Al-easa, Hala S.; Mann, John; Rizk, Abdel-Fattah ( Elsevier , 1990 , Article  &   Report)
      Three sesquiterpene lactones were isolated from the aerial parts of Centaurea sinaica: amberboin, chlorohyssopifolin A and sinaicin. The latter is reported for the first time.
    • Sesquiterpene lactones from Pulicaria sicula 

      Zdero, C.; Bohlmann, F.; Rizk, A. M. ( Elsevier , 1988 , Article)
      The aerial parts of Pulicaria sicula afforded the known xanthanolides 1-6, the guaianolides 7 and 8 as well as two new ones, the lactone 9 and the corresponding epoxide 10. Furthermore nerylisobutyrate and the thymol ...