Semi-synthesis, structural elucidation and in-vitro anti-snake venom activity of irregular monoterpenes derivatives from Baccharis trimera (Asteraceae)

Abstract

Irregular monoterpenes are rare natural products found mainly in the Asteraceae family, whose skeleton does not follow the Ruzicka rule, which establishes a head-to-tail bond between the isoprene units [1]. Of the different types of terpenoids with reordered skeleton, those with an o-menthane skeleton are very rare, with the most relevant members being piquerols A and B from Piqueria trinervia Cav. and carquejol from Baccharis trimera (Less.) DC. (synonym: B. genistelloides) [2] (Figure 1) both plants belonging to the Asteraceae.