Occurrence and Biological Activities of Eremophilane-type Sesquiterpenes

Abstract

As important members of the terpenes family, sesquiterpenes represent a group of natural compounds with diverse skeletal types. Among them, the eremophilane-type sesquiterpenes, widely present in several genera (such as Ligularia, Senecio, Cacalia) of Asteraceae, account for a small number of natural compounds and form differently from other sesquiterpenes because they challenged the isoprene rule of biosynthesis. Due to the unique structural features and various functional groups, these compounds possess a number of biological activities such as anti-tumor, anti-bacterial and anti-inflammatory, having received increasing interest in the recent years. This review summarizes the occurrence of eremophilane-type sesquiterpenes and research progresses on their biological activities since the 1990 s.

Eremophilane Sesquiterpenes from a Deep Marine-Derived Fungus, Aspergillus sp. SCSIOW2, Cultivated in the Presence of Epigenetic Modifying Agents

“…They are also widely found from fungi species. These compounds are of interest because many of them showed a wide range of pharmaceutical functions including phytotoxic, cytotoxic, anti-bacterial, anti-microbial, anti-inflammatory, anti-allergic, and so on [16]. Macrophages play major roles in the immune responses by releasing various factors such as pro-inflammatory cytokines and nitrogen species.…”

“…Eremophilane type sesquiterpenes belong to bicyclic sesquiterpenes, containing only two complete isoprene subunits, are present in about 20 genera of the Asteraceae family, and can be regarded as the chemotaxonomic markers sources of Ligularia, Senecio, Cacalia, and Petasites genera [16]. They are also widely found from fungi species.…”

Eremophilane Sesquiterpenes from the Genus Ligularia

“…Aside from Ligularia , eremophilanes are also present in other genera of the same family Compositae, Senecio , Cacalia , and Petasites , in particular. Only a few have been identified from Jubulaceae, Lamiaceae, Scrophulariaceae, Thymelaeaceae, and Zingiberaceae families .…”

Total Synthesis of the Polyoxygenated Sesquiterpenes Guignarderemophilanes C and D

“…The first member of this family had been isolated and reported by J. L. Simonsen and coworkers in 1932, and named eremophilone . Since this discovery, many new compounds bearing this structural motif have been described, featuring a number of biological activities such as anti‐inflammatory, anti‐tumor or anti‐bacterial . Structural diversity for eremophilane sesquiterpenes, as for terpenes in general, is generated by a variety of oxidation events taking place during biosynthesis.…”

“…Neither of these compounds have been synthesized yet and there is no reported preparative strategy addressing this unusual trihydroxylated A-ring motif. Recently, two natural products with a 1a,2b,3b-trihydroxylated scaffold have been isolated for the first time from the fungus Guignardia mangiferae, and named guignarderemophilanes C (1) and D (2). [9] The fungus Guignardia mangiferae is an endosymbiont of plants such as Gelsemium elegans, whose extracts are used in traditional Chinese medicine as nervous relaxant and for the treatment of pain.…”