Ketoesters are organic compounds that contain both a ketone and an ester functional group. They are formed through a reaction between a ketone and an alcohol, resulting in a structure that features a carbonyl group (C=O) and an ester group (RCOOR'). Ketoesters are important in various chemical processes and can serve as intermediates in the synthesis of other organic compounds. In biochemistry, ketoesters play a role in metabolic pathways, particularly in the Krebs cycle and fatty acid synthesis. They can also be involved in the production of ketone bodies, which are used as an alternative energy source during periods of low carbohydrate intake, such as in the ketogenic diet.