1) Ester 
A depside is a type of polyphenolic compound composed of two or more monocyclic aromatic units linked by an ester bond. Depsides are most often found in lichens, but have also been isolated from higher plants, including species of the Ericaceae, Lamiaceae, Papaveraceae and Myrtaceae. Depsides have antibiotic, anti-HIV, antioxidant, and anti-prolif...
any of a group of esters formed from two or more phenol carboxylic acid molecules.