3 9,19-CYCLOTETRACYCLIC TRITERPENES FROM SKIMMIA-WALLICHII

Phytochemical studies on Skimmia wallichii resulted in the isolation o f skimmiwallichin, skimmiwallin and a new cycloartanol type compound s kimmiwallinin. The structure of skimmiwallinin is elucidated as 3 oxy- 24-methyl-24-ethyl-9,19-cyclolanost-25(26)-ene on the basis of spectra l studies. The structures of skimmiwallichin and another tetracyclic t riterpene, now named skimmiwallin, were revised and established to be 3 -methoxy-24,24-diethyl-9,19-cyclolanost-25(26)-ene and 3 eta-methoxy -25-ethyl-9,19-cyclolanost-24(24')-ene, respectively. Copyright (C) 19 96 Elsevier Science Ltd