Graphical Abstract: This review presents a synthetic transformations of ent-kaurane diterpenes, covering various aspects of the chemical and microbiologically transformations of native ent-kaur-16-en-19-oic acid, namely, its reactions via COOH groups, double bonds and rearrangements of the carbon skeleton, what we offer a wide range of natural and synthetic derivatives potentially biologically actives and convenient synthon for their synthesis.