ester

1. (organic chemistry) A compound most often formed by the condensation of an alcohol and an acid, with elimination of water, which contains the functional group carbon-oxygen double bond (i.e., carbonyl) joined via carbon to another oxygen atom.Examples: "To produce a test material containing at least 75 percent omega-3 polyunsaturates, the menhaden triglycerides are transesterified to produce fatty acid ethyl esters. The esters are reacted with urea dissolved in hot ethanol and the solution is cooled overnight."; "The thiol-coenzyme-A ester formed by R-arylpropionic acid can bind to triglyceride to form a “hybrid” triglyceride: such hybrid triglycerides can cause alteration of fatty-acid metabolism and membrane function, and a lipophilic triglyceride–propionic-acid hybrid would be able to cross lipid membranes such as the blood–brain barrier."; "The effort’s primary material systems are vinyl esters and polyurethanes, reinforced with inexpensive chopped-glass rovings. Automated glass-fiber preforming processes and high-rate molding procedures are being studied in an effort to reduce cycle times and production costs substantially."