The PentacyclicTriterpenes, α, β-amyrins: A Review of Sources and Biological Activities

Pentacyclic triterpenes are ubiquitously distributed throughout the plant kingdom, in a free form as aglycones or in combined forms, and have long been known to have a number of biological effects. The compounds alpha-amyrin and beta-amyrin are commonly found in medicinal plants and oleo-resin obtained by bark incision of several species of Bursera or Protium of the Burseraceae family. Both in vitro and in vivo studies have shown that beta- amyrin also has important biological functions. In light of the considerable interest recently generated in the chemistry and pharmacological properties of amyrins and their analogs, we have undertaken this review in an effort to summarize the available literature on these promising bioactive natural products. The review will detail the recent studies on the chemistry and bioactivity of alpha, beta-amyrins, which is presented in the following sections: the isolation and distribution of alpha-amyrin and beta-amyrin, giving a brief introduction to amyrins as natural products and the methods used in their isolation; the biological activities of amyrins, examining the biological properties associated with these compounds with a focus on their potential chemotherapeutic applications.