Concept explainers
Interpretation:
The structure of lactose sugar based on the given experimental evidences is to be shown.
Concept introduction:
舧 Chair conformations: It is the most stable conformation, which accurately shows the spatial arrangement of atoms.
舧 Equatorial bonds are parallel to the average plane of the ring, while axial bonds are perpendicular to the average plane of the ring.
舧 The conformation having bonds at the equatorial positions are more stable than those with bonds at the axial position.
舧 On flipping the cyclohexane ring, axial bonds become equatorial bonds and equatorial bonds becomes axial bond.
舧 Bulkier group acquires equatorial positions to form stable conformer due to steric factors.
舧 The most stable configuration of aldopyranoses is when the
舧 Stereochemistry: The equatorial orientation refers to the spatial arrangement of
舧 The anomeric effect is lowest for sugars with equatorial orientation, which results in lower energetic state, and consequently this type of orientation confers higher stability.
舧 The anomeric effect is highest for sugars with axial orientation, which results in higher energetic state, and consequently this type of orientation confers lower stability.
舧 A carbohydrate is a
舧
舧 Carbohydrates are oxidized by
舧 Aldaric acids are carbohydrates having two carboxylic acids. They are formed due to oxidation reaction of aldoses with dilute
舧 Monosaccharides containing six carbon atoms and an aldehyde group are called aldohexoses.
舧 Alditols are compounds produced from aldoses or ketoses on reduction with certain reagents such as sodium borohydride (
舧
舧 Compounds formed by the reaction of reducing sugars with excess of phenyl hydrazine are called osazones. Osazones are products of oxidation and are produced by all reducing sugars.
舧
舧 Fischer projection is a way of representing the structural formulae of compounds through cross formulation of their open chain structures.
舧 Bromine water is an effective reagent that selectively oxidizes the
舧 Lactose is a disaccharide carbohydrate present in milk (mammary glands) of the mammals. It has a reducing nature and undergoes hydrolysis to yield
舧 The aldehyde group of an aldose reacts with three moles of phenylhydrazine to produce phenylosazone at
舧 The monosaccharides with five or more carbons atoms form cyclic structures in aqueous solution, and they can form two cyclic stereoisomers from each straight-chain monosaccharide, known as anomers. In aqueous solution, the two anomers and the straight-chain structure of a monosaccharide form an equilibrium mixture through the process of mutarotation.
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