SUMMARY
Pentacyclic triterpenes are produced by arrangement of squalene epoxide. These compounds are
extremely common and are found in most plants. There are at least 4000 known triterpenes. Many
triterpenes occur freely but others occur as glycosides (saponins) or in special combined forms.
Pentacyclic triterpenes have a wide spectrum of biological activities and some of them may be
useful in medicine. The therapeutic potential of three pentacyclic triterpenes - lupeol, betuline and
betulinic acid - is discussed in this paper. Betulinic acid especially is a very promising compound.
This terpene seems to act by inducing apoptosis in cancer cells. Due to its apparent specificity for
melanoma cells, betulinic acid seems to be a more promising anti-cancer substance than drugs like
taxol.
KEY WORDS
pentacyclic triterpene; lupeol; betuline; betulinic acid; biological activity
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