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Carboxylation Reaction Vitamin K Cycle
Carboxylation is a chemical reaction in which a carboxylic acid is produced by treating a substrate with carbon dioxide. The opposite reaction is decarboxylation. In chemistry, the term carbonation is sometimes used synonymously with carboxylation, especially when applied to the reaction of carbanionic reagents with CO2. More generally, carbonation usually describes the production of carbonates. Organic chemistry Carboxylation is a standard conversion in organic chemistry. Specifically carbonation (i.e. carboxylation) of Grignard reagents and organolithium compounds is a classic way to convert organic halides into carboxylic acids. Sodium salicylate, precursor to aspirin, is commercially prepared by treating sodium phenolate (the sodium salt of phenol) with carbon dioxide at high pressure (100 atm) and high temperature (390 K) – a method known as the Kolbe-Schmitt reaction. Acidification of the resulting salicylate salt gives salicylic acid. : Many detailed procedures are des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more products, which usually have properties different from the reactants. Reactions often consist of a sequence of individual sub-steps, the so-called elementary reactions, and the information on the precise co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Syntheses
''Organic Syntheses'' is a peer-reviewed scientific journal that was established in 1921. It publishes detailed and checked procedures for the synthesis of organic compounds. A unique feature of the review process is that all of the data and experiments reported in an article must be successfully repeated in the laboratory of a member of the editorial board as a check for reproducibility prior to publication. The journal is published by Organic Syntheses, Inc., a non-profit corporation. An annual print version is published by John Wiley & Sons on behalf of Organic Syntheses, Inc. History Prior to World War I, work on synthetic organic chemistry in the United States had been quite limited, and most of the reagents used in laboratories had to be imported from Europe. When export stoppages and trade embargoes cut off this source, Clarence Derick, a professor of chemistry at University of Illinois at Urbana-Champaign, began an effort to synthesize these needed chemicals in industrial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posttranslational Modification
Post-translational modification (PTM) is the covalent and generally enzymatic modification of proteins following protein biosynthesis. This process occurs in the endoplasmic reticulum and the golgi apparatus. Proteins are synthesized by ribosomes translating mRNA into polypeptide chains, which may then undergo PTM to form the mature protein product. PTMs are important components in cell signaling, as for example when prohormones are converted to hormones. Post-translational modifications can occur on the amino acid side chains or at the protein's C- or N- termini. They can extend the chemical repertoire of the 20 standard amino acids by modifying an existing functional group or introducing a new one such as phosphate. Phosphorylation is a highly effective mechanism for regulating the activity of enzymes and is the most common post-translational modification. Many eukaryotic and prokaryotic proteins also have carbohydrate molecules attached to them in a process called glycosyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institutes Of Health
The National Institutes of Health, commonly referred to as NIH (with each letter pronounced individually), is the primary agency of the United States government The federal government of the United States (U.S. federal government or U.S. government) is the national government of the United States, a federal republic located primarily in North America, composed of 50 states, a city within a fede ... responsible for biomedical and public health research. It was founded in the late 1880s and is now part of the United States Department of Health and Human Services. The majority of NIH facilities are located in Bethesda, Maryland, and other nearby suburbs of the Washington metropolitan area, with other primary facilities in the Research Triangle Park in North Carolina and smaller satellite facilities located around the United States. The NIH conducts its own scientific research through the NIH Intramural Research Program (IRP) and provides major biomedical research fundin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
