What is carbohydrate chemistry?
carbohydrate chemistry describes the structure, properties and reactions of carbon, hydrogen and oxygen compounds known as carbohydrates. These compounds have a general formula C (H 2 o) n , where n can be any number from three up. It can be seen that carbohydrates always contain hydrogen and oxygen in water ratios (H 2 o), ie a part of the "hydrate" of the name. Carbohydrates include sugars, starch, cellulose and many other common substances. They are made of carbon dioxide and water with photosynthesis in plants and are an essential source of energy in the diet of all animals. However, carbohydrate chemistry can be quite complex because it can be connected with the number of small carbohydrate molecules to form much larger structures. Simple carbohydrates such as glucose are known as monosaccharides. The chemistry of carbohydrates has progressed significantly when the details of the structure of many monosaccharides were first clarified by German chemist Emil Fischer at the end of the 19th century. Complex carbohydrates consist of monosaccharide unitsjoined together.
Moleculesconsisting of two monosaccharides are known as disaccharides; A common example is sucrose - better known as table sugar - which consists of monosaccharides of glucose and fructose. Oligosaccharides have several monosaccharide units and polysaccharides consist of long chains of these units, sometimes numbing thousands; Examples are starch in various forms and cellulose. Each molecular unit in the chain is associated with its neighbor glycosidic binding, which consists of removal of hydrogen (H) and hydroxyl (OH) groups - forming water - from neighboring molecules of monosaccharides.
carbohydrate structures are such that different molecules can have the same oversoll formula, with atoms arranged differently. For example, monosaccharides can be divided into ALDOSES that have a group and aldehyde groups, and ketosis that have a group of keto-two carbon oxygen linkIf as a carbonyl group. Although glucose and fructose have the same chemical formula (C 6 h 12 6 ), they are differently structured: glucose is aldose and fructose is ketosis. This is a common feature of carbohydrate chemistry.
It is also possible for carbohydrates to exist in various forms. Glucose may have a linear form, with six carbon atoms being a short chain; Carbon atoms can be numbered C1-C6, with C1 forming a group of aldehydes and C6 at the other end associated with two hydrogen atoms and a hydroxyl group. Four carbon atoms between each of them have a hydrogen atom on one side and a hydroxyl group on the other side. There are two forms of glucose, D-glucose and L-glucose, which differ only in the fact that the former maybe one of his hydroxyl groups on the same side of the molecule as the aldehydium oxygen, while in the other this arrangement is precisely perverted. This applies to many monosaccharides, while the forms of "D" predominate among natural sugars.
In the solution, d-glucose tends to form a circular structure, with a C6 pushed to one side and a hydroxyl group on the C5 reacting with the ALDEHDA group on the C1 in such a way that it is made up of a six-otom ring with 5 carbon atoms and oxygen atom. This is known as a ring of glucopyranosis. The ring may have two different forms, depending on the position of the hydroxyl group on the C1. If it is on the same plane as the ring, the compound is known as P d-Gluopyranosis, but if it lies perpendicular to the plane of the circle, it is known as and D-Glumopyranosis. Two different forms are known as anomers and carbon atom C1 is known as an an anomery carbon.
The form β looks more structurally stable and in the case of D-Glucopyranosis is, but in some monosaccharides the form and form are more common. This is because in these compounds the electrostatic forces between electron pairs in the anomeric hydroxyl group and the oxygen atom in the circle can overcome greater structural stability of β form, a phenomenon known as an anomeric effect. ThatThe form is more stable, depending not only on the compound, but also on solvent and temperature.
Hydroxyl, aldehyde and keto in carbohydrates can be replaced by other groups, allowing a wide range of reactions. Carbohydrates form the basis of many other biologically important compounds. For example, ribosis and deoxyribosis, related compound, are basic units from which DNA and RNA nucleic acids are formed. Glycosides are made of carbohydrates and alcohols; Fischer glycosidation, named after Emil Fischer, includes the use of a catalyst to create a glycoside methyl glucoside of glucose and methanol. Another way to produce glycoside is Koenigs-Knororor reaction, which combines glycosylhaalogenide with alcohol to form glycoside.