*3.2.1.1.4. Callitrisic acid*

Callitrisic acid is a diterpenoid acid contained in the resins of several *Callitris* species (Cupressaceae). It was simultaneously reported as a new natural product [53, 54]. This acid also occurs in plants of the genus *Juniperus* and *Calceolaria*, and it has also been found in the genus *Illicium*. Recently, a series of related acids to callitrisic acid having a C-19 carboxylic group have been isolated [55].

Biological activity: All these acids demonstrated important antiviral activity and significant anti-inflammatory activity [56].
