| Popis: |
Eleven tetranortriterpenoids were isolated from the heartwood of X. rumphii and were identified as the limonoids, xylorumphiins L (RH.1), E (RH.2) and C (RH.3) and tetranortriterpenoids, xylorumphiins M-S (RH.4-10). Compounds RH.4-10 have a hemiacetal group which opens and closes in solution making it impossible to purify. Acetylation enabled separation of the R and S forms. Separation of the acetylated mixtures RH.4-10 led to the isolation of four acetylated derivatives of RH.4 (RH.4a-d), two acetylated derivatives of RH.5 (RH.5a and 5b), one acetylated derivative of RH.6 (RH.6a), two acetylated derivatives of RH.7 (RH.7a and 7b), one acetylated derivative of RH.8 (RH.8a) and one acetylated derivative of RH.10 (RH.10a). Compounds RH.1 and RH 4-10 have not been described previously. |
