Synthetic Alkaloids: Cantharidin Derivatives

Cantharidin is a naturally occurring cyclic anhydride found in many insect species, particularly Lytta vesicatoria, known as the Spanish fly. Although highly poisonous, dried Spanish fly has been used as an aphrodisiac since ancient Greeks and Romans. Spanish fly has been used in eastern medicine for many years as a natural anticancer agent, especially in the treatment of hepatoma and esophageal carcinoma. Over time, its stotoxicity was determined to be high and its use was limited. Later, alkaloid derivatives with no stotoxic effect were produced synthetically and evaluated as anticancer agents. Since cantharidin obtained from insects is not an alkaloid but its derivatives with lower stotoxicity, cantharimide and norcantharimide are cyclic imides, they can be evaluated in the class of alkaloids. Cantharimide and norcantharimide compounds have gained importance in terms of their stotoxic effect on many cancer cell lines. Many studies have been done on their synthesis and anticancer properties for many years.