Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.
Solution and Explanation
(1) Aldehydes give 2, 4-DNP test, Schiff's test, and react with NaHSO4to form the hydrogen sulphite addition product. However, glucose does not undergo these reactions.
(2) The pentaacetate of glucose does not react with hydroxylamine. This indicates that a free -CHO group is absent from glucose.
(3) Glucose exists in two crystalline forms - ∝andβ. The ∝-form (m.p. = 419 K) crystallises from a concentrated solution of glucose at 303 K and the β-form (m.p = 423 K) crystallises from a hot and saturated aqueous solution at 371 K. This behaviour cannot be explained by the open chain structure of glucose.
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Concepts Used:
Glucose
Glucose is a simple sugar, also known as dextrose, that is a primary source of energy for living organisms. It is a monosaccharide, meaning it consists of a single sugar unit, and is chemically classified as an aldohexose, which means it has six carbon atoms and an aldehyde functional group.
Glucose is produced by plants through the process of photosynthesis, where it is synthesized from carbon dioxide and water using energy from sunlight. It is also produced in the human body through the breakdown of complex carbohydrates, such as starch and glycogen, in the process of digestion.
Glucose is transported throughout the body via the bloodstream and taken up by cells where it is metabolized to produce energy in the form of ATP. Excess glucose can be stored in the liver and muscles as glycogen for later use.
Read Also: Structure of Glucose and Fructose
Glucose is an important component of many foods, such as fruits, honey, and sweetened beverages. It is also used as a sweetener in the food industry and as a medical treatment for hypoglycemia, a condition characterized by low blood glucose levels.
Measurement of glucose levels in the blood is an important diagnostic tool for monitoring and managing diabetes, a chronic metabolic disorder characterized by high blood glucose levels. Glucose testing can be done using a variety of methods, such as fingerstick testing and continuous glucose monitoring.