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An ester of a carboxylic acid.R stands for any group (typically hydrogen or organyl) and R ′ stands for any organyl group.. In chemistry, an ester is a compound derived from an acid (organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group (−OH) of that acid is replaced by an organyl group (R ′). [1]
Esters of carboxylic acids with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties, while polyesters are important plastics, with monomers linked by ester moieties.
Estradiol, the base estrogen of most estrogen esters. This is a list of estrogen esters, or ester prodrugs of estrogens. It includes esters, as well as ethers, of steroidal estrogens like estradiol, estrone, and estriol and of nonsteroidal estrogens like the stilbestrols diethylstilbestrol and hexestrol.
In organic chemistry and biochemistry esters are the functional group (R'-COOR") consisting of an organic radical united with the residue of any oxygen acid, either organic or inorganic. An ester is a product of the reaction of an acid (usually organic) and an alcohol (the hydrogen of the acid R-COOH is replaced by an alkyl group R").
Estrogen esters are essentially inactive themselves, with esters such as estradiol valerate and estradiol sulfate having about 2% of the affinity of estradiol for the estrogen receptor. [12] Likewise, the estrogen ether mestranol (ethinylestradiol 3-methyl ether) has about 1% of the affinity of estradiol for the estrogen receptor. [12]
Active esters are often used in peptide synthesis, e.g., N-hydroxysuccinimide, hydroxybenzotriazole. [1] Active esters of acrylic acid are precursors to polymers with reactive side chains. [4] The concept of active esters extends to esters of phosphoric and sulfuric acids. One such case is dimethylsulfate, a strong methylating agent.
Esters of fatty acids are colorless, although degraded samples are sometime appear to be yellow or even brown. The triglycerides are powders, flakes, coarse powders, or granular or waxy lumps, oils or liquids. They are almost odorless. Biodiesels are typically fatty acid esters made by the transesterification of vegetable fats and oils. In this ...
Cholesteryl esters are a type of dietary lipid and are ester derivatives of cholesterol. The ester bond is formed between the carboxylate group of a fatty acid and the hydroxyl group of cholesterol. Cholesteryl esters have a lower solubility in water due to their increased hydrophobicity. Esters are formed by replacing at least one –OH ...