Oleananetype

Oleananetype refers to a class of natural products that share the oleanane pentacyclic triterpenoid skeleton. This skeleton, a C30 terpenoid framework, forms the core of many oleanane-type compounds found in plants and fungi. Derivatives vary by oxidation, hydroxylation, glycosylation, and other substitutions.

Biosynthesis of oleanane-type triterpenoids begins with the mevalonate pathway producing squalene, which is oxidized to 2,3-oxidosqualene and cyclized by beta-amyrin synthase to give the oleanane-type skeleton. Subsequent enzymes introduce functional groups such as hydroxyl, carbonyl, or carboxyl groups, or attach sugar moieties to form saponins and other conjugates.

Natural occurrence of oleanane-type triterpenoids is widespread in the plant kingdom, appearing in leaves, fruits, bark, and roots. Notable members include oleanolic acid, maslinic acid, and glycyrrhetinic acid. Olives (Olea europaea) are a well-known source of oleanane-derived compounds, while glycyrrhetinic acid is common in licorice (Glycyrrhiza species). The group also appears in a diverse range of other plants, contributing to a variety of natural products with different substitution patterns.

Properties and uses of oleanane-type triterpenoids span pharmacology, chemotaxonomy, and industrial applications. They have been studied for anti-inflammatory, hepatoprotective, and other biological activities, especially in vitro. As scaffolds, they serve as models in drug discovery and as constituents in cosmetics and nutraceuticals. In plant chemistry, oleanane-type compounds are valuable for understanding biosynthetic pathways and plant taxonomy.