Chemical and Biological Aspects of the Natural 1,4-Benzoquinone Embelin and its (semi-)Synthetic Derivatives

Abstract

Like the impressive biological properties of embelin, its chemical aspects have raised the interest of scientists in the field as well. A detailed understanding of the chemistry of embelin is necessary to fully exploit it medicinally. Search for embelin isolation and its chemical modifications was carried out using web-based literature searching tools such as Pubmed and Scifinder. Pertinent literature is covered up to 2016. Structures of bioactive embelin derivatives are provided. Pure embelin, obtained from Embelia ribes berries extraction or by total synthesis, was applied for a number of biological assays. Semi-synthetic and total synthetic approaches led to new high affinity embelin-derived inhibitors of crucial protein targets and to new embelin derivatives with improved pharmacological properties (e.g., with better water-solubility or as applications for drug carrier systems). This review provides a summary of the rich chemistry of embelin and the latest developments in the field of optimized (semi-)synthetic embelin derivatives including their biological activities.