Alpha-D-glucose is one of the stereoisomers of glucoses, specifically the D-glucoses.
alpha-D-glucose, dextrose, monosaccharide, carbohydrate, sugar, simple sugar, stereoisomer, hexose, glycoside, aldose, aldohexose, silver mirror test, constitution, conformation, axial, equatorial, photosynthesis, starch, organic chemistry, chemistry
Molar mass: 180.16 g/mol
Melting point: 146 °C
Density: 1.5620 g/cm³
Heat of combustion: -2,805 kJ/mol
Alpha-D-glucose is an aldohexose. It is a white, odourless, sweet, crystalline compound, which dissolves well in water but poorly in alcohol. When heated, it melts at a low temperature. The ring structure contains an ether and a hydroxyl group.
’Alpha’ means that the hydroxyl group attached to the first carbon atom is located below the plane of the ring, opposite the CH₂OH group. In beta-D-glucose the hydroxyl group and the CH₂OH group are located on the same hemisphere.
’D’ means that the chiral centre farther from the oxo group has the same configuration as in D-glyceraldehyde.
Alpha-D-glucose forms esters with carboxylic acids. It gives positive results for the Fehling’s and Tollens’ tests since some of the rings open up in an aqueous solution, and the resulting open chain molecules take part in the reaction.
Occurrence and production
Glucose is found in almost all sweet fruits, it is a component of di-, and polysaccharides such as maltose and starch.
It is produced in plants during photosynthesis.
The human body uses the energy produced during the slow metabolic breakdown (or biological oxidation) of glucose. It is used in large quantities in several chemical syntheses, such as the production of sorbitol, gluconic acid, ascorbic acid, and glutamic acid.
A helical molecule consisting of alpha-D-glucose units. It is one of the basic components of starch.
The primary source of energy for living cells.
The animation demonstrates the process of ring closure of open-chain glucose into alpha- and beta-D-glucose.
A type of sugar found in mammalian milk.
A disaccharide formed by the joining of two alpha-D-glucose molecules.
A white, water-soluble, sweet compound known as sugar.
Fructose is the sweetest of the simple carbohydrates.
One of the stereoisomers of D-glucose.
Cellobiose is the basic structural unit of cellulose.
The building material of the cell walls and fibres of plants.
An exercise about the groups and structure of mono-, di- and polysaccharides.
Mirror image isomers of asymmetrical shapes and solids are non-superimposable.
Plants are capable of converting inorganic substances (carbon dioxide and water) into organic sugar.
The liver is a vital organ that plays an important role in the digestion of fats, detoxification and metabolism.