Figure 4.

Structures of identified terpenoids with immunomodulatory activities. These terpenoids are distinguished in triterpenoid pentacyclic saponin (7, 8, 9, 13, 20, 21), lactone sesquiterpenoid (10, 11, 12), tetracyclic saponin heterosid (14, 15, 16, 17), pentacyclic saponin heterosid (18), diterpenoid (19) and Acyclic monoterpenoid (22). They have in common adjacent 2–5 rings, except for linalool (22). It is an advantage to have simple and complex structures like in linalool and beta-aescin (18), respectively, exhibiting immunomodulatory activities, which will lengthen the list of analogues.